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Communication Systems/Frequency-Division Multiplexing

Introduction
It turns out that many wires have a much higher bandwidth than is needed for the signals that they are currently carrying. Analog Telephone transmissions, for instance, require only 3 000 Hz of bandwidth to transmit human voice signals. Over short distances, however, twisted-pair telephone wire has an available bandwidth of nearly 100000 Hz!

There are several terrestrial radio based communications systems deployed today. They include:

 * Cellular radio
 * Mobile radio
 * Digital microwave radio

Mobile radio service was first introduced in the St. Louis in 1946. This system was essentially a radio dispatching system with an operator who was able to patch the caller to the PSTN via a switchboard. Later, an improved mobile telephone system, IMTS, allowed customers to dial their own calls without the need for an operator. This in turn developed into the cellular radio networks we see today.

The long haul PSTNs and packet data networks use a wide variety of transmission media including

 * Terrestrial microwave
 * Satellite microwave
 * Fiber optics
 * Coaxial cable

In this section, we will be concerned with terrestrial microwave systems. Originally, microwave links used FDM exclusively as the access technique, but recent developments are changing analog systems to digital where TDM is more appropriate.

Fixed Access Assignment
Three basic methods can be used to combine customers on to fixed channel radio links:

 * FDMA - (Frequency division multiple access) analog or digital
 * TDMA - (Time division multiple access) three conversation paths are time division multiplexed in 6.7 mSec time slots on a single carrier.
 * CDMA - (Code division multiple access) this uses spread spectrum techniques to increase the subscriber density. The transmitter hops through a pseudo-random sequence of frequencies. The receiver is given the sequence list and is able to follow the transmitter. As more customers are added to the system, the signal to noise will gradually degrade. This is in contrast to AMPS where customers are denied access once all of the frequencies are assigned code division multiple access [digital only]

 * [[Image:Fixed_assgnment_access.gif]]

What is FDM?
Frequency Division Multiplexing (FDM) allows engineers to utilize the extra space in each wire to carry more than one signal. By frequency-shifting some signals by a certain amount, engineers can shift the spectrum of that signal up into the unused band on that wire. In this way, multiple signals can be carried on the same wire, without having to divy up time-slices as in Time-Division Multiplexing schemes.In analog transmission, signals are commonly multiplexed using frequency-division multiplexing (FDM), in which the carrier bandwidth is divided into subchannels of different frequency widths, each carrying a signal at the same time in parallel

Traditional terrestrial microwave and satellite links employ FDM. Although FDM in telecommunications is being reduced, several systems will continue to use this technique, namely: broadcast & cable TV, and commercial & cellular radio.

Analog Carrier Systems
The standard telephony voice band [300 – 3400 Hz] is heterodyned and stacked on high frequency carriers by single sideband amplitude modulation. This is the most bandwidth efficient scheme possible.

 * [[Image:Single_voice_channel.gif]]

The analog voice channels are pre-grouped into threes and heterodyned on carriers at 12, 16, and 20 kHz. The resulting upper sidebands of four such pregroups are then heterodyned on carriers at 84, 96, 108, and 120 kHz to form a 12-channel group.

Since the lower sideband is selected in the second mixing stage, the channel sequence is reversed and a frequency inversion occurs within each channel.

 * [[Image:12_channel_group.gif]]

This process can continue until the available bandwidth on the coaxial cable or microwave link is exhausted.

 * [[Image:Analog_carrier_systems.gif]]

In the North American system, there are:

 * 12 channels per group
 * 5 groups per supergroup
 * 10 super groups per mastergroup
 * 6 master groups per jumbogroup

In the European CCITT system, there are:

 * 12 channels per group
 * 5 groups per supergroup
 * 5 super groups per mastergroup
 * 3 master groups per supermastergroup

There are other FDM schemes including:

 * L600 - 600 voice channels 60–2788 kHz
 * U600 - 600 voice channels 564–3084 kHz
 * L3 - 1860 voice channels 312–8284 kHz, comprised of 3 mastergroups and a supergroup
 * L4 - 3600 voice channels, comprised of six U600s

Benefits of FDM
FDM allows engineers to transmit multiple data streams simultaneously over the same channel, at the expense of bandwidth. To that extent, FDM provides a trade-off: faster data for less bandwidth. Also, to demultiplex an FDM signal requires a series of bandpass filters to isolate each individual signal. Bandpass filters are relatively complicated and expensive, therefore the receivers in an FDM system are generally expensive.

Examples of FDM
As an example of an FDM system, Commercial broadcast radio (AM and FM radio) simultaneously transmits multiple signals or "stations" over the airwaves. These stations each get their own frequency band to use, and a radio can be tuned to receive each different station. Another good example is cable television, which simultaneously transmits every channel, and the TV "tunes in" to which channel it wants to watch.

Orthogonal FDM
Orthogonal Frequency Division Multiplexing (OFDM) is a more modern variant of FDM that uses orthogonal sub-carriers to transmit data that does not overlap in the frequency spectrum and is able to be separated out using frequency methods. OFDM has a similar data rate to traditional FDM systems, but has a higher resilience to disruptive channel conditions such as noise and channel fading.


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Communication Systems/What is Modulation?

Modulation is a term that is going to be used very frequently in this book. So much in fact, that we could almost have renamed this book "Principles of Modulation", without having to delete too many chapters. So, the logical question arises: What exactly is modulation?

Definition
Modulation is a process of mixing a signal with a sinusoid to produce a new signal. This new signal, conceivably, will have certain benefits over an un-modulated signal. Mixing of low frequency signal with high frequency carrier signal is called modulation.

 * $$f(t) = A \sin(\omega t + \phi)$$

we can see that this sinusoid has 3 parameters that can be altered, to affect the shape of the graph. The first term, A, is called the magnitude, or amplitude of the sinusoid. The next term, $$\omega$$ is known as the frequency, and the last term, $$\phi$$ is known as the phase angle. All 3 parameters can be altered to transmit data.

The sinusoidal signal that is used in the modulation is known as the carrier signal, or simply "the carrier". The signal that is used in modulating the carrier signal(or sinusoidal signal) is known as the "data signal" or the "message signal". It is important to notice that a simple sinusoidal carrier contains no information of its own.

In other words we can say that modulation is used because some data signals are not always suitable for direct transmission, but the modulated signal may be more suitable.

Types of Modulation
There are 3 basic types of modulation: Amplitude modulation, Frequency modulation, and Phase modulation.
 * amplitude modulation
 * a type of modulation where the amplitude of the carrier signal is modulated (changed) in proportion to the message signal while the frequency and phase are kept constant.

 * frequency modulation
 * a type of modulation where the frequency of the carrier signal is modulated (changed) in proportion to the message signal while the amplitude and phase are kept constant.

 * phase modulation
 * a type of modulation where the phase of the carrier signal is varied accordance to the low frequency of the message signal is known as phase modulation.

Why Use Modulation?
Why use modulation at all? To answer this question, let's consider a channel that essentially acts like a bandpass filter: both the lowest frequency components and the highest frequency components are attenuated or unusable in some way, with transmission only being practical over some intermediate frequency range. If we can't send low-frequency signals, then we need to shift our signal up the frequency ladder. Modulation allows us to send a signal over a bandpass frequency range. If every signal gets its own frequency range, then we can transmit multiple signals simultaneously over a single channel, all using different frequency ranges.

Another reason to modulate a signal is to allow the use of a smaller antenna. A baseband (low frequency) signal would need a huge antenna because in order to be efficient, the antenna needs to be about 1/10th the length of the wavelength. Modulation shifts the baseband signal up to a much higher frequency, which has much smaller wavelengths and allows the use of a much smaller antenna.

Examples
Think about your car radio. There are more than a dozen (or so) channels on the radio at any time, each with a given frequency: 100.1 MHz, 102.5 MHz etc... Each channel gets a certain range (usually about 0.22 MHz), and the entire bayot gets transmitted over that range. Modulation makes it all possible, because it allows us to send voice and music (which are essential baseband signals) over a bandpass (or "Broadband") channel.

Non-sinusoidal modulation
A sine wave at one frequency can be separated from a sine wave at another frequency (or a cosine wave at the same frequency) because the two signals are "orthogonal".

There are other sets of signals, such that every signal in the set is orthogonal to every other signal in the set.

A simple orthogonal set is time multiplexed division (TDM) -- only one transmitter is active at any one time.

Other more complicated sets of orthogonal waveforms—Walsh codes and various pseudo-noise codes such as Gold codes and maximum length sequences—are also used in some communication systems.

The process of combining these waveforms with data signals is sometimes called "modulation", because it is so very similar to the way modulation combines sine waves with data signals.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


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Communication Systems/Analog vs. Digital

There is lots of talk nowadays about buzzwords such as "Analog" and "Digital". Certainly, engineers who are interested in creating a new communication system should understand the difference. Which is better, analog or digital? What is the difference? What are the pros and cons of each? This chapter will look at the answers to some of these questions.

What are They?
What exactly is an analog signal, and what is a digital signal?

 * Analog : Analog signals are continuous in both time and value. Analog signals are used in many systems, although the use of analog signals has declined with the advent of cheap digital signals. All natural signals are Analog in nature or analog signal is that signal which amplitude on Y axis change with time on X axis...

or digital signal is that signal which have certain or fixed value on Y axis change with time on X axis...
 * Digital : Digital signals are discrete in time and value. Digital signals are signals that are represented by binary numbers, "1" or "0". The 1 and 0 values can correspond to different discrete voltage values, and any signal that doesn't quite fit into the scheme just gets rounded off.

Digital signals are sampled, quantized & encoded version of continuous time signals which they represent. In addition, some techniques also make the signal undergo encryption to make the system more tolerant to the channel.

What are the Pros and Cons?
Each paradigm has its own benefits and problems

 * Analog : Analog systems are less tolerant to noise, make good use of bandwidth, and are easy to manipulate mathematically. However, analog signals require hardware receivers and transmitters that are designed to perfectly fit the particular transmission.
 * Digital : Digital signals are more tolerant to noise, but digital signals can be completely corrupted in the presence of excess noise. In digital signals, noise could cause a 1 to be interpreted as a 0 and vice versa, which makes the received data different than the original data. Imagine if the army transmitted a position coordinate to a missile digitally, and a single bit was received in error. This single bit error could cause a missile to miss its target by miles.  Luckily, there are systems in place to prevent this sort of scenario, such as checksums and CRCs, which tell the receiver when a bit has been corrupted and ask the transmitter to resend the data.  The primary benefit of digital signals is that they can be handled by simple, standardized receivers and transmitters, and the signal can be then dealt with in software (which is comparatively cheap to change).

Discrete data has a fixed set of possible values.
 * Discrete Digital and Analogue:

Digital data is a type of Discrete data where the fixed value can either be 1 or 0.

Analogue data can take on any real value.

Sampling and Reconstruction
The process of converting from analog data to digital data is called "sampling". The process of recreating an analog signal from a digital one is called "reconstruction". This book will not talk about either of these subjects in much depth beyond this, although other books on the topic of EE might, such as A-level Physics (Advancing Physics)/Digitisation.


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Communication Systems/Communication Mediums

Signals need a channel to follow, so that they can move from place to place. These Communication Mediums, or "channels" are things like wires and antennae that transmit the signal from one location to another. Some of the most common channels are listed below:

Twisted Pair Wire
Twisted Pair is a transmission medium that uses two conductors that are twisted together to form a pair. The concept for the twist of the conductors is to prevent interference. Ideally, each conductor of the pair basically receives the same amount of interference, positive and negative, effectively cancelling the effect of the interference. Typically, most inside cabling has four pairs with each pair having a different twist rate. The different twist rates help to further reduce the chance of crosstalk by making the pairs appear electrically different in reference to each other. If the pairs all had the same twist rate, they would be electrically identical in reference to each other causing crosstalk, which is also referred to as capacitive coupling. Twisted pair wire is commonly used in telephone and data cables with variations of categories and twist rates.

Other variants of Twisted Pair are the Shielded Twisted Pair cables. The shielded types operate very similar to the non-shielded variety, except that Shielded Twisted Pair also has a layer of metal foil or mesh shielding around all the pairs or each individual pair to further shield the pairs from electromagnetic interference. Shielded twisted pair is typically deployed in situations where the cabling is subjected to higher than normal levels of interference.

Coaxial Cable
Another common type of wire is Coaxial Cable. Coaxial cable (or simply, "coax") is a type of cable with a single data line, surrounded by various layers of padding and shielding. The most common coax cable, common television cable, has a layer of wire mesh surrounding the padded core, that absorbs a large amount of EM interference, and helps to ensure a relatively clean signal is transmitted and received. Coax cable has a much higher bandwidth than a twisted pair, but coax is also significantly more expensive than an equal length of twisted pair wire. Coax cable frequently has an available bandwidth in excess of hundreds of megahertz (in comparison with the hundreds of kilohertz available on twisted pair wires).

Originally, Coax cable was used as the backbone of the telephone network because a single coaxial cable could hold hundreds of simultaneous phone calls by a method known as "Frequency Division Multiplexing" (discussed in a later chapter). Recently however, Fiber Optic cables have replaced Coaxial Cable as the backbone of the telephone network because Fiber Optic channels can hold many more simultaneous phone conversations (thousands at a time), and are less susceptible to interference, crosstalk, and noise then Coaxial Cable.

Fiber Optics
Fiber Optic cables are thin strands of glass that carry pulses of light (frequently infrared light) across long distances. Fiber Optic channels are usually immune to common RF interference, and can transmit incredibly high amounts of data very quickly. There are 2 general types of fiber optic cable: single frequency cable, and multi-frequency cable. single frequency cable carries only a single frequency of laser light, and because of this there is no self-interference on the line. Single-frequency fiber optic cables can attain incredible bandwidths of many gigahertz. Multi-Frequency fiber optics cables allow a Frequency-Division Multiplexed series of signals to each inhabit a given frequency range. However, interference between the different signals can decrease the range over which reliable data can be transmitted.

Wireless Transmission
In wireless transmission systems, signals are propagated as Electro-Magnetic waves through free space. Wireless signals are transmitted by a transmitter, and received by a receiver. Wireless systems are inexpensive because no wires need to be installed to transmit the signal, but wireless transmissions are susceptible not only to EM interference, but also to physical interference. A large building in a city, for instance can interfere with cell-phone reception, and a large mountain could block AM radio transmissions. Also, WiFi internet users may have noticed that their wireless internet signals don't travel through walls very well.

There are 2 types of antennas that are used in wireless communications, isotropic, and directional.

Isotropic
People should be familiar with isotropic antennas because they are everywhere: in your car, on your radio, etc... Isotropic antennas are omni-directional in the sense that they transmit data out equally (or nearly equally) in all directions. These antennas are excellent for systems (such as FM radio transmission) that need to transmit data to multiple receivers in multiple directions. Also, Isotropic antennas are good for systems in which the direction of the receiver, relative to the transmitter is not known (such as cellular phone systems).

Directional
Directional antennas focus their transmission power in a single narrow direction range. Some examples of directional antennas are satellite dishes, and wave-guides. The downfall of the directional antennas is that they need to be pointed directly at the receiver all the time to maintain transmission power. This is useful when the receiver and the transmitter are not moving (such as in communicating with a geo-synchronous satellite).


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Communication Networks/Circuit Switching Networks

Old folks may very well remember the first incarnation of the telephone networks, where an operator sitting at a desk would physically connect different wires to transmit a phone call from one house to another house. The days however when an operator at a desk could handle all the volume and all the possibilities of the telephone network are over. Now, automated systems connect wires together to transmit calls from one side of the country to another almost instantly.

What is Circuit-Switching?
Circuit switching is a mechanism of assigning a predefined path from source node to destination node during the entire period of connection. Plain old telephone system (POTS) is a well known example of analogue circuit switching.

Strowger Switch
Strowger Switch is the first automatic switch used in circuit switching. Prior to that all switching was done manually by operators working at various exchanges. It is named after its inventor Almon Brown Strowger.

Telephony
This is a telephone thing


text: User talk:198.91.39.205

title: User talk:198.91.39.205


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User talk:Nivritchari

Welcome
Come introduce yourself at the new users page. If you have any questions, you can ask there or contact me personally.

Template:Npov
Don't delete contents of templates. They are used on whole Wikibooks. --Derbeth 20:24, 7 November 2005 (UTC)

Copyright problem with Image:Arabic.jpg
--Derbeth 20:24, 7 November 2005 (UTC)

 * I have to remind you of image descriptions. Every image must have source, author and proper license template. Images with unknown status can be deleted. --Derbeth 12:05, 8 November 2005 (UTC)

Please stop uploading images with unknown source. You can't get any image and just upload it to Wikibooks. Most images are copyrighted and cannot be used at Wikibooks. You can upload an image only if
 * 1) You are it's author and you release it under free license (write you're the author and give propoper tag); or
 * 2) Images was released as public domain or GFDL (provide link to source and give proper tag)

Using copyrighted images is dangarous to Wikibooks because it can lead to lawsuits agains us. If you continue uploading images without proper copyright information, you will be blocked from editing Wikibooks. Furthermore, images with improper description can be deleted at any time. --Derbeth 20:58, 11 November 2005 (UTC)

 * I blocked you for one day - please wait and come back tomorrow. I don't understand why are you ignoring my warnings; you can ask me if you want, but you don't and keep uploading improper images. There are warnings at upload page - you're ignoring them too. If you don't agree with my decision, you can contact other administrators by e-mail (they can unblock you) or visit IRC channel to talk with me.

 * Consider using Wikimedia Commons - you don't have to upload any images, just use image from Commons like they were uploaded here. Look at commons:Image:Phnom Wan.jpg and commons:Image:Khmer wat (temple) 2 by skawimp.jpg. --Derbeth 21:33, 11 November 2005 (UTC)

Image:Mideast.jpg
Do you have larger version of this map? It's hard to see details on it. --Derbeth 20:24, 7 November 2005 (UTC)

Again image problems
I see you uploaded new images. You gave description to Image:Atlantis.jpg, but you've done it on page where you used it. We write license information at image page. See Image:Wizoz house.jpg how it should look like. Again: if you don't understand something, you can write to me.

Another problem is with copyright status of Image:Atlantis.jpg. You wrote "Copyright Lee Krystek 1997" - that's a problem. We do not accept copyrighted work, even "used by permission". Author must explicitly license his work under GFDL (or Creative Commons) license, or realease his work to public domain. If this image is copyrighted, we will delete it. --Derbeth talk 18:47, 17 November 2005 (UTC)

Hittites
I'm transporting your King List from Wikijunior Ancient Civilizations/Hittites to Wikibooks' Ancient History/Hittites. Any chance you'd be interested in writing a more formal piece for the Ancient History book? Andrew Watt 22:40, 2 June 2006 (UTC)

title: User talk:Nivritchari


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Talk:Blogging/Welcome

I think the all-caps headlines are a little bit annoying. I dont know, however, if there is policy against it. is it necessary? removing the all-caps would make the page look better. --Whiteknight T C E 21:49, 7 November 2005 (UTC)

That's just what I was going to say. I also find the caps hard to read.

I quite agree. Professoryak (talk) 16:14, 18 April 2009 (UTC)

Couldn't agree more. Is it OK to change them? CgSeif323 (discuss • contribs) 21:28, 7 November 2011 (UTC)

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User talk:Halavais~enwikibooks

Copyright problem with Image:Uses and Gratifications fig2.png
--Derbeth 22:25, 7 November 2005 (UTC)

 * Well, fair use isn't forbidden at Wikibooks. But I'm not sure if taking images from printed books can be qualified as fair use. Using logos and screenshots - yes - but schemas? I think the best solution would be redrawing them. Fair use makes problems with f.e. printing a book. --Derbeth 23:34, 7 November 2005 (UTC)

Your account will be renamed
Hello,

The developer team at Wikimedia is making some changes to how accounts work, as part of our on-going efforts to provide new and better tools for our users like cross-wiki notifications. These changes will mean you have the same account name everywhere. This will let us give you new features that will help you edit and discuss better, and allow more flexible user permissions for tools. One of the side-effects of this is that user accounts will now have to be unique across all 900 Wikimedia wikis. See the announcement for more information.

Unfortunately, your account clashes with another account also called Halavais. To make sure that both of you can use all Wikimedia projects in future, we have reserved the name Halavais~enwikibooks that only you will have. If you like it, you don't have to do anything. If you do not like it, you can pick out a different name.

Your account will still work as before, and you will be credited for all your edits made so far, but you will have to use the new account name when you log in.

Sorry for the inconvenience.

Yours, Keegan Peterzell Community Liaison, Wikimedia Foundation 23:12, 17 March 2015 (UTC)

Renamed
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User:Redlentil/CoobookNav2

Cookbook | Cookbook:

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text:
Template:Edit2

[ edit ]

Usage
Like but with an extra parameter to modify the "edit" message.

Example
"" yields

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Template talk:Edit2

Usage
Like Template:Edit but with an extra parameter to modify the "edit" message.

"" yields

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Angels and Demons/Divergence from reality

In the beginning of the book, Brown claims that "references to all works of art, tombs, tunnels, and architecture in Rome are entirely factual (as are their exact locations). They can still be seen today. The brotherhood of the Illuminati is also factual." While the book does not specifically say that all of its apparently factual statements are true, Brown's assertions regarding his extensive research have led some readers to take the fictional universe of the book to be congruent to reality.

However, in many ways the fictional universe of the book's storyline significantly diverges from reality.

Historical Divergences

 * Langdon asserts incorrectly that Michelangelo designed the outfits for the Swiss Guards, though this is a common misconception. According to its official site, Commandant Jules Repond (1910–1921) designed the uniforms influenced by the Renaissance artist Raphael.
 * Langdon claims that the Illuminati were founded in the 15th century and that Galilei who died in 1642, along with other eminent scientists, was a member of the group. He further asserts that in 1668, four eminent scientists who were members of the group were gruesomely executed in an event he calls the purga. In fact the Illuminati, a short-lived enlightenment era secret society, were only founded in 1776 and outlawed in 1784.
 * Even though they do have a security as well as ceremonial role inside the Vatican, Brown's depiction of the Swiss Guard as a crack special ops squad, along the lines of the SAS, carrying out operations around the city of Rome (outside Vatican jurisdiction) is inaccurate.
 * In a flashback, Langdon recalls a lecture he gave in his Symbology 212 class where he tells his class that "The practice of 'god-eating' — that is, Holy Communion — was borrowed from the Aztecs." It's unclear how this could have occurred, as communion has its roots in the Last Supper (ca. AD 30) and the Aztec culture did not rise until the 14th century. Even if the Aztecs had been around when the practice of communion began, there is no evidence of contact between Europeans and the inhabitants of Central America at that time. The first clear evidence of European contact with these people occurred after Christopher Columbus reached the New World in 1492.
 * Brown states that Winston Churchill was a Roman Catholic. Churchill was an non-observant member of the Church of England. He was not a "pillar of the church" but a "flying buttress". "I support it from the outside."
 * Langdon recalls "that much of Galileo's legal trouble had begun when he described planetary motion as elliptical. The Vatican exalted the perfection of the circle and insisted that heavenly motion must be only circular." In reality Galileo famously refused to believe in his friend Kepler’s elliptical orbits and Galileo's clash with the Vatican was a result of his support for Heliocentrism, that is claiming that the Earth orbited the Sun and not vice versa. Galileo's support for heliocentricity might not have caused such a fuss if the Church hadn't needed to present a unified front against the threat of the Protestant Reformation, and Galileo causing dissent at home in Rome only made the Church respond more finally to the new science.
 * Glick explains that George H.W. Bush must be a member of the Illuminati because he was a 33° Freemason. Neither Bush has ever been a Freemason, though both were members of the Skull & Bones fraternity at Yale.
 * Brown mentions in a dialogue between Langdon and Kohler that Copernicus was 'murdered by the church for revealing scientific truths'. Copernicus, as a matter of fact, was a Polish priest and was encouraged by other clergymen to publish his findings. He died a natural death, and there is no evidence suggesting that he was murdered.
 * The Hashshashin hired by the novel's villains refers to Christians as playing a critical role in the downfall of his sect. This is inaccurate; the Hashshashin were crippled by invading Mongols when their fortress of Alamut in modern-day Iran was destroyed in 1256.
 * There is no such publication as the British Tattler. The Tatler, note the spelling, is well known and would not need to be described as "British" to be identified.
 * Brown states that the Isola Tiberina was thought to have healing powers ever since 1656. However, the people of ancient Rome had already built a temple to Aesculapius, the Greek god of healing, on the island in the third century BC.

Location Divergences

 * CERN does not have a private airport or any aeroplanes especially an X-33 spacecraft. In fact, the X-33 was only produced as a sub-scale technology demonstrator and was never actually built full-scale.
 * Dan Brown claims that "Bernini's city-wide cross of obelisks marked the fortress in perfect Illuminati fashion; the cross’s central arm passed directly through the center of the castle’s bridge, dividing it into two equal halves." In fact, neither of the two arms of the cross go through the Castel Sant'Angelo. In all likelihood, Brown was using a topographical tourist map to design this plot element and had not realised that the physical layout was different (and such a map would not have been in print for the designers of the city).
 * While in the church of Santa Maria del Popolo, Langdon thinks, "Renaissance cathedrals invariably contained multiple chapels, huge cathedrals like Notre Dame having dozens." This leads the reader to believe that the architecture of the Notre Dame cathedral in Paris is of the Renaissance period.  In fact, Notre Dame is the most famous example of Gothic architecture in the world, which pre-dates the Renaissance period. (Brown also seems to assume that all churches in Rome are cathedrals. The term "cathedral" is reserved for those churches where a bishop has his throne (or "cathedra"). The one (Roman Catholic) cathedral in Rome is St John Lateran—and not St Peter's in the Vatican).
 * A straight line extending south west of Piazza del Popolo does not pass through the centre of St. Peter's Square, nor does it even pass through Vatican City.
 * The Saint Peter's Basilica's crypt (Grotte Vaticane), where most Popes are entombed, is open to the public.
 * The BBC headquarters is not (as the novel states) located in Piccadilly; the main BBC headquarters is Broadcasting House in Langham Place, just north of Oxford Circus, and there are also headquarters buildings for the BBC World Service (Bush House, in Aldwych) and for BBC Television (the Television Centre, in White City). Although the latter is in a sense "west of Piccadilly Circus", it is several miles to the west, not immediately west as the novel's wording implies.

Religious Divergences

 * Brown claims that hatha yoga was an ancient Buddhist art. Although influenced by Buddhism, Hatha Yoga pre-dates Buddhism and instead originates from Hinduism. It was, and is, a Hindu art.
 * In examining the body of the previous Pope, the Swiss Guard simply slide back the marble top of the tomb and they check the tongue of the Pope. In fact, Popes are buried in three nested coffins, which would have made this task somewhat more difficult.
 * The novel asserts several non-facts about the process of a Papal conclave. It is suggested that only cardinals may be elected in a conclave. This is not true, any male Roman Catholic may be elected. It is further suggested that four candidates, whom he calls preferiti are semi-formally chosen, including a head, to become the candidates for papacy, thus making the Conclave obsolete. This is again not true; although there are papabili (generally, cardinals considered to have a chance of being elected), there are no formal candidates before the beginning of the conclave. Further, ballots are restricted to two in the morning and two in the evening, each group is burned together. Dan Brown indicates they are burned individually and indicates that more than two may occur in a single evening. The ballots are read out by one cardinal, verified by another, and pierced by a third; the book suggests that a single person does all of these. The Cardinals do not stay in the Sistine Chapel overnight. They go back to Domus Sancta Marta after two ballots in the morning and two ballots in the evening (in the case a pope hasn't been elected in those ballots). Brown gives the role of camerlengo to the late Pope's secretary. The camerlengo does organize the Conclave but he is never the pope's secretary. In fact, the camerlengo is a member of the College of Cardinals and is pre-chosen by the pope to take charge of the affairs during the Sede Vacante. The late Pope's secretary has no authority over anyone in the Vatican, as he loses his job when the pope dies. Also, the book states that the "Dean of the College of Cardinals" of the conclave cannot be elected; in fact, he can, and he actually was in the 2005 conclave (then Cardinal Ratzinger was the Dean of the College of Cardinals). It should also be noted that the "Devil's Advocate" has nothing to do with the papal election but with the process of beatification. Langdon's encounters with the camerlengo take place in the Papal Apartments, while in fact the rules order that the apartments be sealed during the Conclave and the late Pope's staff has to live somewhere else.
 * At the end of the novel, Glick reports that the camerlengo was elected pope for a short time through something called "election by adoration." This is probably meant to refer to the process of election "by acclamation or inspiration" (Latin: per acclamationem seu inspirationem), which was explicitly prohibited as a form of Papal election in 1996, when Pope John Paul II released the apostolic constitution Universi Dominici Gregis.  This document also forbids the election of a pope by compromise or committee (Latin: per compromissum), leaving only the secret balloting of conclave as a legitimate form of election.
 * Concerning Cardinal (Kardinal) Ebner from Frankfurt (the first victim): There are two major cities in Germany that are called Frankfurt (in addition to small one(s)): Frankfurt am Main and Frankfurt an der Oder. None of them are one of Germany's dioceses and therefore none of the Frankfurts have a bishop. It is not a necessity to be a bishop in order to be chosen to become a cardinal, but that is of course with absolute majority the case. In Germany there are two theologians who became cardinals (the rest were bishops): Alois Kardinal Grillmeier and Leo Kardinal Scheffczyk. So theoretically it is possible that there is someone from Frankfurt who was chosen to become a cardinal. But more likely is that Dan Brown made a rather common mistake: Frankfurt am Main has a big church in its center called "Dom" (cathedral). A cathedral (German: "Dom" or "Kathedrale") is the central church of a diocese and the bishop's seat. Therefore it is not uncommon that people think Frankfurt is a diocese and has a bishop. But in this case the term "Dom" was used as a general description of a large and historically important church. The name of the Frankfurt Dom is "St. Bartholomäus" (Bartholomew) (see: Kaiserdom St. Bartholomäus). Everyone refers to that church though as "Dom" or "Kaiserdom" (Emperor's Cathedral), because from 1562 to 1792 ten German emperors were crowned in that church. Strictly speaking though the use of the word "Dom" is wrong.
 * Cardinal's cassocks are not black as those of ordinary priests, but scarlet.
 * Brown refers to the Biblical Book of Judges as the Book of Judgments.
 * In a flashback in the novel, the late pope confesses to Carlo Ventresca that he, the pope, has a son. Ventresca, waiting for no further explanation, rushes out, distraught at his mentor's broken vows (see "vows" below). Later in the novel, Cardinal Mortati tries to reassure Ventresca that the pope's love (and that of his beloved, the nun, Sister Maria) was chaste, since Ventresca was conceived without sexual intercourse, by means of artificial insemination, thereby ensuring that both parents remained faithful to their vows. This explains the former pope's love of and support for science, since it enabled him to remain a celibate priest whilst becoming a father. Artificial insemination is forbidden by the Catholic Church and is considered sinful, since it separates conception from the sex act, and also (usually) requires masturbation for the gathering of sperm.
 * Strictly speaking, nuns, monks, friars, etc (i.e., all those consecrated to religious life), take "vows" to God, while diocesan clergy make "promises" (including celibacy), to their bishop.
 * Italian Laws do not allow singles to adopt a child; a catholic priest like Leonardo Vetra could not adopt Vittoria as a daughter giving her his surname.

Scientific Divergences

 * The proton is not, as stated in the book, the antiparticle of the electron. The proton is the antiparticle of the antiproton; the electron is the antiparticle of the positron.
 * The process of creating antimatter described in the book is inaccurate. Instead of colliding two particles moving in opposite directions, CERN smashes protons into a stationary block of copper or iridium.
 * It is impossible to create and sustain the densities of antimatter described in the book. In fact, it takes 2 billions years to create that much of antimatter. Similarly, antimatter could never be used as a source of power. Antimatter has to be created since it is found nowhere on Earth naturally. The amount of energy required to operate the particle accelerator would be far greater than (or, ideally, equal to) the energy the antimatter-matter reaction would produce. To produce antimatter with less energy than it released would be in violation of the 1st law of Thermodynamics, so even a "ground breaking discovery" as described in the book occurred, it would not be physically possible.
 * Brown writes that the antimatter canister will detonate with the energy of a 5 kiloton bomb. However, the energy released will be from the total consumption of 0.5g of material; 0.25g of antimatter, and 0.25g of normal matter.  This has the energy equivalent of about 1013 Joules, or about 10 kilotons of TNT. The Hiroshima bomb was about 20 kilotons. The Nagasaki bomb was 13 kilotons.
 * Containment of hydrogen (anti- or otherwise) in a magnetic field would not be possible in a small portable container. For the hydrogen to form a droplet at normal temperatures and in a vacuum (as would be necessary to isolate it from normal matter) would require a magnetic field of extraordinary strength, beyond the power of a portable power source.  This magnetic field would have to extend well beyond the canister and would cause vigorous effects on ferromagnetic materials nearby.  Furthermore, hydrogen in its conventional liquid state is diamagnetic, and would be difficult to suspend unless the compression induced by the magnetic field caused the hydrogen to become metallic (as in the core of gas giant planets).
 * Having jumped out of a helicopter seconds before a ten kiloton antimatter annihilation, Camerlengo Ventresca would most likely have been vaporised. If not, then the explosion would have propelled him at such a speed that there would be absolutely no chance of his slowing enough to land safely.
 * Annihilation of protons and anti-protons would generate energy primarily in the form of 900 [MeV gamma rays. These gamma rays would easily penetrate the matter surrounding the bomb and deliver a lethal dose of radiation to any exposed person standing closer than 2–3 km from the point of explosion.
 * Near the end of the novel, Brown repeats the popular notion that humans only use a small percentage of their brains. In fact, this is a myth.

Technological Divergences

 * The pilot explains Langdon's nausea is altitude sickness from flying at 60,000 ft (18,288 m). "Altitude sickness" is not due to altitude but to (lack of) air pressure. A properly pressured aircraft should not induce altitude sickness. Many Concorde passengers flew at 60,000 ft without experiencing altitude sickness.
 * Rather than being the mature transport system described in the book, the Lockheed Martin X-33 is, in fact, a small unmanned technology-demonstration vehicle. Intercontinental hypersonic spaceplanes are planned, but none exist.
 * Arguably the most blatant and central error made in the book concerns the wireless camera which occupies a central role in the search for the antimatter canister. In the book, the canister is supposedly being filmed by a wireless camera and that signal is being displayed on a large screen in St. Peter's square. In order to find this camera, the Swiss Guard needs to shut off every electronic device to and conduct a painstaking search for the camera, which is eventually found, with the canister, deep underground in a labyrinth of tombs beneath the Vatican. There are several problems with this plot line.  First, if the wireless camera's signal is being received and the picture displayed in St. Peter's Square, then it would not take more than a few minutes for a trained team of engineers to triangulate the position of the transmission. Indeed, consider the countless movies about World War II clandestine radio operators who could not transmit more than a few minutes at a time so as not to be detected by the counter-intelligence triangulation teams. Here we have a camera that is transmitting for hours. The rule is: if you can receive the signal, it is very easy to find out where it comes from.  The other, second and perhaps greater error is the fact that this wireless camera is transmitting from underground. Transmission of a video signal takes a lot a bandwidth and hence must have a relatively high carrier frequency (such as VHF, UHF, or SHF). In the book we are told that we can see the canister's display counting down in seconds in real-time, which means that we are indeed talking about a relatively high bandwidth signal, and hence, the assumption of a high carrier frequency is a good one. Such carrier frequencies cannot penetrate any significant obstacles and hence it is simply impossible for the signal of such a camera to be received if it were transmitting from deep underground. Indeed, it would be virtually impossible to receive a signal from deep underground even if a very low frequency carrier were to have been used. In conclusion, the whole premise of the plot, namely a laborious search for a canister which is being filmed by a wireless camera from deep underground, does not stand the scrutiny of basic radio transmission principles. ''
 * There is the lack of a method for recharging the anti-matter canister. A container requiring electrical power to function designed both to be easily portable and to hold such quantities of dangerous material would have the option to use an alternate method to recharge the on-board battery, preferably one that can be as easily employed as a standard "wall wart" power adapter and an electrical outlet. Without a similar option, the canisters themselves are shockingly unsafe for their stated function from an engineering standpoint and pay little heed to Murphy's Law.
 * The author appears to confuse the invention of the World Wide Web by Tim Berners-Lee at CERN in the 1980s with the invention of the Internet mainly in the US in the 1960s. Far from being unrecognised for his work as is implied in the book Tim Berners-Lee has received numerous awards including appointment to the Order of the British Empire as a Knight Commander (KBE). He is also head of the W3C which manages and defines the most popular WEB standards.
 * Cellular phones do not have dial tones. Furthermore, cellphone calls cannot be made untraceably as suggested in the book; whenever a cellphone is switched on, even if it is in standby mode, the service provider can detect which cell it is in and hence where it is to within a few metres.
 * "Illuminati: New World Order", the game mentioned in the book, is a Collectible card game, not a computer game. Steve Jackson Games is not a computer game company. It is not playable on the internet, and one does not score points by killing opponents.

Cultural Divergences

 * Gunther Glick, the supposedly "British" journalist, has speech and thoughts which are riddled with Americanisms (e.g. "gas" instead of "petrol", "anchormen" instead of "presenters"), and in a fantasy about future success, he likens himself to Dan Rather — who is relatively unknown in Britain. A real British journalist would probably most likely liken himself to Trevor McDonald.
 * The Atom/element of Botswan's construction *()

Translation Errors

 * Langdon states at one point that the phrase Novus Ordo Seclorum, found on American currency, translates as "New Secular Order." The correct translation is "New Order of the Ages."
 * Langdon tells Kohler that the Church declared the Illuminati "Shaitan," which he identifies as an "Islamic word." In fact, the word "Shaitan" (Arabic شيطان) comes from ancient Hebrew "ha Satan," (standard Hebrew  In Hebrew, Shaitan translates to "adversary". In Islamic culture, the word refers to anyone who has rebelled against God.
 * Robert Langdon incorrectly translates Seraphim as "The Fiery One". In reality, Seraphim is the plural form of Seraph. This is a commonly made error.
 * The assassin uses a word, "Tabban", it is meant to be a curse in Arabic that translates to something like the expression "Damn" in English, though some mix it with Arabic word "Tab'aan" which is simply a commonly used emphatic statement meaning 'of course'


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Talk:Angels and Demons/Divergence from reality

List of factual inaccuracies of the book Angels and Demons authors and history

 * 2005-11-07 05:30:12 User:Hektor
 * 2005-11-07 05:29:36 User:Hektor
 * 2005-11-07 04:23:37 User:Hektor
 * 2005-11-07 04:22:51 User:Hektor
 * 2005-11-07 04:22:24 User:Hektor
 * 2005-11-07 04:21:47 User:Hektor
 * 2005-11-07 04:20:59 User:Hektor
 * 2005-11-07 04:20:19 User:Hektor
 * 2005-11-07 04:20:00 User:Hektor
 * 2005-11-07 04:19:20 User:Hektor
 * 2005-11-07 04:18:35 User:Hektor
 * 2005-11-07 04:18:17 User:Hektor
 * 2005-11-07 04:04:51 User:Superm401 (afd)
 * 2005-11-07 03:23:33 User:Hektor
 * 2005-11-07 03:22:34 User:Hektor m (List of factual inaccuracies of Angels and Demons moved to List of factual inaccuracies of the book Angels and Demons)
 * 2005-11-07 03:22:16 User:Hektor

= From Wikipedia:Talk:List of factual inaccuracies of the book Angels and Demons = Please see Talk:Angels and Demons for an explanation of the genesis of this article.Hektor 03:30, 7 November 2005 (UTC)

Internet vs the WWW.
While Tim Berners-Lee did not invent the Internet, the book never claimed that he did. It merely referenced the World Wide Web. (You can check pages 7 and 20-21 of the book, depending on which version you have.)

May I suggest we bring this paragraph over from Wikipedia:

 * CERN states another often-percieved misunderstanding in the book is the reference to CERN as the organization that invented the Internet, when in fact, Tim Berners-Lee and a small team at CERN invented the hypertext transport protocol that led to the World Wide Web, not the Internet, which was engineered in the United States by DARPA. However, the character Maximilian Kohler claims only that CERN indeed invented the Web, and a plaque later repeats this point. The book never mentions CERN as the inventor of the Internet.

Incorrect wording? Precision vs. resolution
One of the technical errors reads as follows:

 * It is impossible yet to create a device that would measure the charge remaining in a battery so accurately, that it could show the time remaining to battery exhaust with the precision of 1 second.

Surely that should read "...with a resolution of 1 second"? (Or better still, "one second".) My understanding of the terms "precision", "accuracy" and "resolution" is that although related, they are different; the smallest unit of measurement an instrument can discern is the resolution of the instrument, whilst if one were to do a series of tests with the instrument and then subtract each result obtained from the result which should have been obtained, the accuracy of the instrument is given by the arithmetic mean of the differences whilst the precision is given by the standard deviation. -- 92.40.32.106 (talk) 13:21, 21 May 2009 (UTC)

Cellular phones
what does the sentence "Cellular phones do not have dial tones" means?
 * "Cellular phones" is another name for the devices which are also called "cellphones" or "mobile phones" (the latter being the most common name for them in the UK). — 92.40.6.56 (talk) 12:18, 15 July 2009 (UTC)

We in law enforcement only wish we could locate a cell phone within a few meters in seconds. Sorry, that is just not true.

Technology seconds about Wifi camera
The author of this article confuses latency with bandwidth. Having the ability to transmit something near real time is latency. Being able to transmit the data with enough resolution and shaking as shown in the movie is both a combination of Bandwidth and Latency.

Microwave devices can be use to achieve both such latency and bandwidth. Though the transmission through solid rock would make receiving such signal pretty difficult.


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Angels and Demons

Welcome to the wiki-based annotated text and analysis Wikibook for the novel Angels and Demons by Dan Brown.

Contents

 * /Background/ — background information on the mythology upon which the book is based
 * /Divergence from reality/ — where and how the book diverges from reality

Book goals

 * Offer critical commentary and analysis of the book presented to help others better understand detailed situations

เทวากับซาตาน

title: Angels and Demons


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Angels and Demons/Background

This is a guide to the real events, things, and ideas that the book uses as parts of its storyline and setting, and how they are used in the book.

 * The secret brotherhood at the heart of the book is the Illuminati.
 * The Lockheed Martin X-33 was a real space launch vehicle, whose prototype was 85% complete before NASA cancelled the project.
 * CERN
 * Freemasonry
 * Henry A. Wallace was the Vice President of the United States and is alleged to be a Freemason who caused the Illuminati symbol to be included on U.S. 1 Dollar Bill
 * Antimatter

เทวากับซาตาน/เบื้องหลัง

title: Angels and Demons/Background


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Wikijunior:Ancient Civilizations/Hittites

Who Were They?
The Hittites were a group of Indo-European people whose empire stretched across Turkey, Iraq, Syria and Palestine. Most of modern Turkey is considered to be the home land of the Hittite people. The peak of their civilization was reached from 1600 to 1200 BC. Their civilization ended as suddenly as it started. Originally the Hittites spoke a language similar to Sanskrit, a dead language of India. They were a warrior race notorious for their ferocity and brutality. Because of them Mesopotamia lost its honor as the cradle land of civilization and never emerged at its full strength again.

What Country Did They Live In?
The Hittites were unknown to the modern world until 1900 AD, when a tablet with an unknown inscription was excavated. The tablet was later translated and gave the world the information of their existence. Hattie was their home land and Hattusas was the name of their capital. It is situated in Central Anatolia region of modern Turkey and in the town of Boghazköy about 210 kilometres east of Ankara.

The Hittite lived in present-day Turkey. The Hittite capital was near a village that is now called Bogazkoy. It was between the Mediterranean sea and the Black Sea and known as the Near East. They spread into North Syria from the Mediterranean to the Persian Gulf.

What Did They Eat?
Hittites ate similar food as other Mediterranean people. Their chief food was bread. Meat was also a part of their day to day menu. Rich people used to satisfy their appetite with homemade cheese and various other milk products. They also had barley, wheat grapes, and lots of other meats. Slaves, prisoners of war and other captives would not as a rule eat the very same.

What Did They Wear?
Hittites were strongly influenced by Babylonians; it is easily conceivable that they used to wear similar clothes as the Babylonians. Picture that we have added with this article supports our view. Hittite men wore long cloaks and women had a dress which consisted of two parts similar to a blouse and knee-long skirt. These dresses are still common in Turkey and Middle East

What Did Their Writing Look Like?
Hittites spoke a language belonging to the Indo-European linguistic family. They used Akkadian’s cuneiform writing system to write their language. The first Hittite tablets were discovered in 1906 by German excavators. Within ten years the language had been deciphered, and a sketch of its grammar published. Gradually, the international community of scholars, led by the Germans, expanded the knowledge of the language. The number of common Hittite words that one could translate with reasonable certainty increased gradually. Now we have a good collection of Hittite words that tells us how closely it was related to Indo-Europeans languages.

What Did They Believe?
Hittites were very generous in adopting other people’s religions. Most of the Hittites deities were from Babylonian and Sumerian origins. Whichever nation they have conquered they had included their gods with gods of Hittites, looks like they believed that gods whoever their worshipper are all legitimate therefore worthy of getting their allegiance. In fact the Hittites probably were the world’s first nation having an attitude of religious tolerance.

What Did Their Buildings Look Like?
Art and architecture of Hatti was strongly influenced by neighbouring countries. They used stone and brick as well as wooden columns to erect their houses and temples. The Hittites built large palaces, temples and fortifications, where carved reliefs adorned walls, gates and entrances. The style was very solid and they tended to go for a massive look. The cities were usually mapped out in a rectangular format.

When did their civilization exist?
The Hittites were a warlike empire that was in existence from 1600 BC until they were raided and destroyed by The sea people in 1200 BC

Hittite Kingship
Pithana early 18th c. Anitta son of Pithana mid 18th c. Labarna first known Hittite king 1680-1650 Hattusili I nephew/adopted son of Labarna 1650-1620 Mursili I grandson/adopted son of Hattusili I 1620-1590 Hantili assassin and brother-in-law of Mursili I 1590-1560 Zidanta I son-in-law of Hantili 1560-1550 Ammuna son of Hantili 1550-1530 Huzziya I son of Ammuna? 1530-1525 Telipinu son of Zidanta I?/brother-in-law of Ammuna 1525-1500 Tahurwaili ? Alluwamna son-in-law of Huzziya I Hantili II son of Alluwamna 1500-1450 Zidanta II ? Huzziya II ? Muwatalli I ? Tudhaliya II son of Huzziya II? 1450-1420 Arnuwanda I son-in-law of Tudhaliya II 1420-1400 Tudhaliya III son of Arnuwanda I 1400-1380 Tudhaliya son of Tudhaliya III 1380? Hattusili II ? ? Suppiluliuma I son of Tudhaliya III or Hattusili II 1380-1340 Arnuwanda II son of Suppiluliuma I 1340-1339 Mursili II son of Suppiluliuma I 1339-1306 Muwatalli II son of Mursili II 1306-1282 Mursili III son of Muwatalli II 1282-1275 Hattusili III son of Mursili II 1275-1250 Tudhaliya IV son of Hattusili III 1250-1220 Karunta son of Muwatalli/cousin of Tudhaliya IV ? Arnuwanda III son of Tudhaliya IV 1220-1215 Suppiluliuma II son of Tudhaliya IV 1215-1200


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High School Mathematics Extensions/Further Modular Arithmetic/Project/Finding the Square Root

Legendre Symbol
.. to be expanded There is actually a simple way to determine whether a is square

Let g be a generator of G where G is the multiplicative group mod p. Since all the squares form a group therefore, if a is a square, then
 * $$a^{\frac{p - 1}{2}} \equiv 1$$

and if a is not a square then
 * $$a^{\frac{p - 1}{2}} \equiv -1$$

we shall use these facts in the next section. .. to be expanded

*Finding the square root*
We aim to describe a way to find a square root in mod m. Let's start with the simplest case, where p is prime. In fact, for square root finding, the simplest case also happens to be the hardest.

If p ≡ 3 (mod 4) then it is easy to find a square root. Just note that if a has a square root then
 * $$(a^{\frac{p + 1}{4}})^2 \equiv a^{\frac{p + 1}{2}} \equiv a^{\frac{p - 1}{2}}a \equiv a $$

So let us consider primes equivalent to 1 mod 4. Suppose we can find the square root of a mod p, and let
 * $$x_0^2 \equiv a \pmod{p}$$

With the above information, we can find the square of a mod p2. We let
 * $$x = x_0 + x_1p \!$$

we want x2 ≡ a (mod p2), so
 * $$x^2 = x_0^2 + 2x_0x_1p + x_1^2p^2 \!$$
 * $$x^2 = a + kp + 2x_0x_1p \pmod{p^2} \!$$

for some k as $$x_0^2 \equiv a \pmod{p}$$ so $$x_0^2 = a + kp$$, we see that
 * $$x^2 = a + p(k + 2x_0x_1) \pmod{p^2} \!$$

so if we need to find $$x_1$$ such that $$k + 2x_0x_1 \equiv 0 \pmod{p} $$, we simply need to make $$x_1$$ the subject
 * $$x_1 \equiv -k(2x_0)^{-1} \pmod{p} $$.

..generalisation ..example

..method for finding a sqr root mod p


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Bartending/Techniques/Highball cocktails

'Highballs' are iced drinks containing liquor and water or a carbonated mixer served in a tall glass. In practice, the term highball is used to refer to any drink prepared in a highball glass with ice. These drinks are prepared directly in a 9 oz (270 mL) highball glass.

Making a highball
Otherwise, if you feel that you're ready for a genuine Spanish "cubata" (rum & coke), you should pour both liquor and mixer 50%-50%. It gives a much stronger taste. It is not really recommended because customers will get drunk fairly quickly, and will stop ordering drinks. It is the usual mix in Spain.
 * Fill a highball glass two-thirds full with ice. Use an ice scoop or your hands; never use the glass.  If the glass breaks in the ice, it will leave shards indistinguishable from ice.  This makes it impossible to locate all of the shards; it is likely that small chips will be scattered through the ice as well as the big pieces.  It may be illegal in your area to use anything but an ice scoop for this reason.
 * Pour in one jigger (45 mL) of liquor. Note:  some bars save money by putting in 1 oz (30 mL) instead of a whole jigger (45 mL).
 * Pour mixer to the top.
 * If the mixer is non-carbonated, stir it; or stick a straw in it and let the drinker stir. If it's carbonated, the bubbles do the stirring for it.
 * Garnish, if necessary.

Highballs with gin

 * Gin and Tonic
 * Gin Highball
 * Gin Buck
 * Gin Rickey
 * Gin and Orange Juice

Highballs with vodka

 * Greyhound


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XML - Managing Data Exchange/WDDX

Learning objectives
Upon completion of this chapter, you will be able to answer the following questions:
 * What is WDDX?
 * What are the uses of WDDX?
 * What are Web Syndicate Networks?
 * What are the benefits of WDDX?

Introduction
WDDX (Web Distributed Data eXchange) was created by Allaire, now known as Macromedia, to solve the problem of exchanging data between different web applications. It was originally intended to be used to exchange data between ColdFusion and other web application languages. This XML-based technology enables complex data to be exchanged between totally different Web programming languages by creating 'Web Syndicate Networks.' WDDX consists of a language-independent representation of data based on an XML 1.0 DTD, and a set of modules for a wide variety of languages that use WDDX.

Features

 * can be used with HTTP, SMTP, POP, FTP and other Internet protocols that support transferring textual data
 * must be using Netscape 3.0+ or Internet Explorer for Windows or any versions for Unix and Mac platforms
 * supports boolean, number, date-time, and string data types
 * supports complex data types like arrays, structures, and recordsets
 * not a formal standard, but is free and widely distributed and is based on standard-base technologies like XML 1.0

How it Works
The way that the web distributed data exchange works is by assigning a specific module for the given programming language to translate the data into an abstract XML format. Another specific module then translates the XML back into another programming language for another web application. For example, if you had an array in a ColdFusion program that you wanted to send to an ASP program, it would first be serialized into XML and sent to the ASP server. The ASP server would then deserialize it and convert it to VBScript for use in the ASP program.

Web Syndicate Networks
The term 'Web Syndicate Network' refers to a group of websites that share their content and transactions. This allows for economies of scale as each site can use shared database content or even transactions and procedures.

title: XML - Managing Data Exchange/WDDX


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Communication Theory/Diffusion of Innovations

Origins of the diffusion paradigm
According to Rogers (1995), the study of the diffusion of innovations (DOI) can be traced back to the investigations of French sociologist Gabriel Tarde (p. 52). Tarde attempted to explain why some innovations are adopted and spread throughout a society, while others are ignored. At the beginning of the twentieth century, Tarde was witness to the development of many new inventions, many of which led to social and cultural change. In his book The Laws of Imitation (1903), Tarde introduced the S-shaped curve and opinion leadership, focusing on the role of socioeconomic status (for example, a cosmopolitan individual is more likely to adopt new products). Even though he did not specify and clarify key diffusion concepts, his insights affected the development of many social scientific disciplines such as geography, economics, and anthropology. Sociologist F. Stuart Chapin, for example, studied longitudinal growth patterns in various social institutions, and found that S-shaped curves best described the adoption of phenomena such as the commission form of city government (Lowery & Defleur, 1995, p. 118).

The basic research paradigm for the diffusion of innovations
The fundamental research paradigm for the diffusion of innovations can be traced to the Iowa study of hybrid seed corn. Bryce Ryan and Neal C. Gross (1943) investigated the diffusion of hybrid seed corn among Iowa farmers. According to Lowery and DeFleur (1995), the background of rural sociology should first be understood before one can discuss how and why the hybrid seed corn study was conducted. The Morrill Act helped “the states establish educational institutions that would be of special benefit to rural youth” (p. 120). Federal funds and other financial supports were given to these land-grant institutions in order to increase the development of the nation’s agricultural industry (p. 120). After World War II, rural sociologists changed their research focus on human problems among farmers because new agricultural technology such as new pesticides, new farm machine, and hybrid seed corn appeared. But in spite of these developments, some farmers ignored or resisted these new innovations. Rural sociologists at land-grant universities in the Midwestern United States such as Iowa State, Michigan State, and Ohio State Universities, performed many diffusion studies to find out the causes of adoption of innovations. One of these efforts was the hybrid seed corn study conducted by Ryan and Gross (1943). These researchers attempted to explain why some farmers adopted the hybrid seed corn, while others did not.

Bryce Ryan and Neal C. Gross
Bryce Ryan earned a Ph. D in sociology at Harvard University. During his doctoral studies, Ryan was required to take interdisciplinary courses in economics, anthropology, and social psychology. This intellectual background helped him conduct the diffusion studies. In 1938, Ryan became a professor at Iowa State University which is known for its agricultural focus. At that time, Iowa State administrators were worried about the slow rate at which the hybrid seed corn was being adopted. Despite the fact that the use of this new innovation could lead to an increase in quality and production, an advantageous adoption by Iowa Farmers was slow. Ryan proposed the study of the diffusion of the hybrid seed corn and received funding from Iowa Agricultural Experiment Station, Iowa State University’s research and development organization. Contrary to previous research, which employed anthropological style approaches using qualitative methods, Ryan employed a quantitative survey method in his study. According to Rogers (1996), Ryan was encouraged to use this quantitative method by “professors in the Department of Statistics, such as Paul G. Homemeyer, Ray J. Jessen, and Snedecor” (p. 415).

When Ryan arrived at Iowa State University, Neal C. Gross was a graduate student who was soon assigned as Ryan’s research assistant. Ryan asked him to conduct interviews with Iowa farmers through survey research. Gross gathered the data from the Iowa communities of Jefferson and Grand Junction. Rogers (1996) mentioned that “by coincidence, these communities were located within 30 miles of where he grew up on a farm” (p. 415). It is also interesting to note that Rogers earned a Ph. D. in sociology and statistics at Iowa State University in 1957.

The Iowa Study of Hybrid Seed Corn: The Adoption of Innovation
As noted above, the hybrid seed corn had many advantages compared to traditional seed, such as the hybrid seed's vigor and resistance to drought and disease. However, there were some barriers to prevent Iowa farmers from adopting the hybrid seed corn. One problem was that the hybrid seed corn could not reproduce (p. 122). This meant that the hybrid seed was relatively expensive for Iowa farmers, especially at the time of the Depression. Therefore, it is reasonable to assume that, despite the economic profit that the hybrid seed corn brought, its high price made a adoption among Iowa farmers remain slow.

According to Lowery and DeFleur (1995), Ryan and Gross sought to explain how the hybrid seed corn came to attention and which of two channels (i.e., mass communication and interpersonal communication with peers) led farmers to adopt the new innovation. They found that each channel has different functions. Mass communication functioned as the source of initial information, while interpersonal networks functioned as the influence over the farmers’ decisions to adopt (p. 125). One of the most important findings in this study is that “the adoption of innovation depends on some combination of well-established interpersonal ties and habitual exposure to mass communication” (p. 127). Ryan and Gross also found that the rate of adoption of hybrid seed corn followed an S-shaped curve, and that there were four different types of adopters. According to Rogers (1995), Ryan and Gross also made a contribution by identifying the five major stages in the adoption process, which were awareness, interest, evaluation, trial, and adoption. After Ryan and Gross’s hybrid corn study, about 5,000 papers about diffusion were published in 1994 (Rogers, 1995).

Medical innovation: Diffusion of a medical drug among doctors
According to Rogers (1996), diffusion theory became more widely accepted after James S. Coleman, Elihu Katz, and Herbert Menzel conducted a study on the diffusion of tetracycline, a new medical drug, in 1966. The Pfizer drug company invented this successful new drug and wanted to investigate the effectiveness of their tetracycline advertisements, which were placed in medical journals. The company asked three professors at Columbia University to find out how physicians adopted the new innovation and how mass communication influenced this adoption process. They conducted a survey to gather accurate and reliable data. Different with previous diffusion research that relied on respondents’ recall of how they adopted new technology, this study gathered data both from physicians' responses and pharmacies' prescription. In addition to this, Coleman et al. (1966) asked their respondents to list their interpersonal connections in order to investigate the effect of interpersonal network links with the new drug adoption. The result shows that the percentage of adoption of the new drug followed an S-shaped curve, but that the rate of tetracycline adoption was faster than the rate of other innovations adoption. The researchers also found that doctors who are cosmopolite were likely to adopt the new drug. One of the most important findings was that doctors who had more interpersonal networks adopted the new medical drug more quickly than those that did not. This meant that interpersonal communication channels with peers had a strong influence on the adoption process. Rogers (1996) noted that this Columbia University study is “one of the most influential diffusion studies in showing that the diffusion of an innovation is essentially a social process that occurs through interpersonal networks” (p. 419). In fact, Rogers (1996) mentioned that even though the study of Ryan and Gross became a milestone in diffusion paradigm, they did not measure the interpersonal network links among farmers. In this case, the Columbia University Drug Study made a contribution to identify the importance of social networks in the diffusion process.

Everett M. Rogers
Rogers was born in Carroll, Iowa in 1931. He earned his B.A., M.A., and Ph.D. degrees from Iowa State University. For two years during the Korean War, he served in the U.S. Air Force. Interestingly, in 1966, he worked on some family planning communication projects in Korea.

One interesting thing worthy mentioning is that Rogers’ father was a farmer who resisted adopting the hybrid seed corn (Singhal, 2005, p. 287). Due to the drought in Iowa in 1936, the Rogers’ farm withered, which made Rogers personally involved in the diffusion research. In the 1950's, Iowa State University was a perfect place for studying the diffusion of innovations, as the school's program focused on a rural sociology, agriculture, and statistics. The experience there led Rogers to dive into the research about why some innovations are adopted while others are ignored. Employed by Michigan State University in 1962, Rogers obtained opportunity to study diffusion in developing countries of Asia, Latin America, and Africa. Meanwhile, he published the book, Diffusion of Innovations, which earned him his academic reputation. Rogers’ comprehensive insights in the book helped to expand diffusion theory. The book has become the standard textbook on diffusion theory and it creats applications of diffusion theory in such fields as geography, economics, psychology, political science, and, as previously mentioned, communication. Rogers retired from University of New Mexico in 2004 because he was suffering from kidney disease. He died on October 21, 2005.

Overview of the diffusion of innovations
According to Rogers (1996), diffusion refers to “the process by which an innovation is communicated through certain channels over time among the members of a social system. An Innovation is an idea, practice or object perceived as new by an individual or other unit of adoption. The diffusion of innovations involves both mass media and interpersonal communication channels” (p. 409). That is, by sharing communication channels such as interpersonal communication or mass communication people can get information of an innovation and perceive its innovation as useful. Lasswell (1948) presented a well-known model of communication that is analyzed as five parts, S-M-C-R-E (e.g., sender-message-channel-receiver-effect). Rogers (1995) mentioned, “this S-M-C-R-E communication model corresponds closely to the elements of diffusion” (p. 19). Specifically, (1) sender can be inventors or opinion leaders, (2) message can be a new idea or product, (3) channels can be interpersonal or mass communication, (4) receivers can be members of a social system, and finally (5) the effects can be individual’s adoption or social change. In the diffusion theory, ‘Time’ variable is a very important factor. According to Rogers (1995), time variable is involved in diffusion in (1) the innovation-decision process; (2) innovativeness; (3) an innovation’s rate of adoption. Most innovations have an S-shaped rate of adoption. Diffusion research has attempted to explain the variables that influence how and why users and audience adopt a new information medium, such as the Internet. According to evolution of media technology, interpersonal influences are important even though in the past the individual is usually the unit of analysis. Also, critical mass becomes an important factor in adopting new media because new media are interactive tools and thus are required by many users to gain efficiency. That is, the more people use, the more people get benefits. In this sense, diffusion theory not only can apply to practical things, but also can be related to digital divide.

There are five different types of adopters in the diffusion process, according to Innovativeness: “(1) Innovators (venturesome), (2) Early Adopters (respectable), (3) Early Majority (Deliberate), (4) Late Majority (skeptical), and (5) Laggards (traditional)” (Rogers, 1995, pp. 183–185). Rogers defined this term as “the degree to which an individual is relatively earlier in adopting new ideas than other members of his social system” (Rogers, 1995, p. 40). Figure 1 shows the relationships between types of adopters divided by innovativeness and their place on the adoption curve. Also, these categories follow a standard deviation curve which is bell-shaped.

Source by www2.gsu.edu/~wwwitr/docs/diffusion/ Figure 2 shows that an innovation would spread through society over various periods of time in a S-shaped curve. However, as noted above, different types of innovations (e.g., the rate of tetracycline adoption is faster than that of the hybrid seed corn) can have their own different rates in diffusion. Figure 2. Shapes of curves of diffusions for innovations

Source by: www.mitsue.co.jp/english/case/concept/02.html

When it comes to the process of innovation-decisions, Rogers (1995) mentioned that there are five stages.

 * 1) Knowledge + or – (selective exposure or awareness of news)
 * 2) Attitudes + or – (people have positive or negative attitude toward innovations)
 * 3) Adoption (Decision): people decide to adopt the innovation
 * 4) Implementation (regular or standard practice)
 * 5) Confirmation (comparing and evaluating)

Rogers introduced perceived characteristics of innovations that consist of (1) relative advantage (2) compatibility (3) complexity (4) triability (5) observability. Based on these five criteria, individuals perceive an innovation as new or useful and decide to adopt it. For example, Rogers (1995) defined relative advantage as “the degree to which an innovation is perceived as better than the idea it supersedes” (p. 15).” New media such as the mp3 will displace conventional media such as CDs or tapes when people perceive new media as advantageous (e.g., low cost or means to be cool). When an individual decides to adopt new media or switch old media with new media, the perceived characteristics of innovations play an important role in reducing some uncertainty about the innovations.

Unit of analysis on diffusion theory
Diffusion of innovation theory attempts to explain how an innovation is spread and why it is adopted at both the micro and macro levels of analysis. Rogers (1996) mentioned, “the individual is usually the unit of analysis, although in recent years a number of studies have been conducted in which an individual organization is the unit of analysis (Wildemuth, 1992; Zaltman, Duncan, & Holbek, 1973)” (p. 418). This characteristic of unit of analysis is due to research methods, such as utilizing a survey to study diffusion. Many studies have focused on individual decisions or adoption. In contrast, diffusion theory considers analysis at both the micro-individual and macro-social levels. This is because studies of diffusion include both an innovation at the micro level, as well as its influence, such as social change, at the macro level.

Rogers (1995) suggested that the four main elements in the diffusion of innovation process were innovation, communication channels, time, and social system. Individuals’ innovativeness, or psychological factors such as communication needs, are analyzed as micro-independent variables. At the macro-social level, this theory assumes that social systems, such as norms, can affect an individual’s adoption or use of an innovation. In terms of communication channels, diffusion of an innovation involves both interpersonal channels (micro) and mass communication channels (macro). By utilizing both mass and interpersonal communication channels, people can get information about an innovation and perceive its usefulness. Therefore, diffusion theory requires both micro-individual and macro-social analysis.

Several diffusion research streams
According to Rice & Webster (2002), ["research and models of the adoption, diffusion, and use of new communication media in organizational settings have arisen from several research streams -- diffusion of innovations, media choice, and implementation of information systems." According to the previous writer of this Wikibook,] we can classify diffusion research and models into three categories: (1) diffusion of innovations (e.g., Rogers, 1995), (2) media choice (e.g., Daft & Lengel, 1986), and (3) implementation of information systems (e.g., Saga & Zmud, 1994). [Unfortunately, one cannot generalize all diffusion research and models with an explanation of diffusion of new communication media.] Table 1 shows that each dependent variable, according to three primary streams of diffusion studies.

Table 1 (Needs to be cleaned up using piping!) The diffusion Of innovation	The Media choice	The Information system Dependent variable	Media adoption Usage	Choice Evaluation	Acceptance User satisfaction Source by: Rice, R., & Webster, J. (2002). Adoption, diffusion and use of new media. In C. Lin and D. Atkin (Eds.), Communication Technology and Society.

That is, the ‘diffusion of innovations’ studies emphasize characteristics of an innovation and the role of communication channels in adopting the innovation, the ‘media choice’ studies focus on the interaction between individual characteristics and social influences in choosing some innovations, and the ‘implementation’ studies assume that the variables such as technology design or ease of use will affect media use (Rice & Webster, 2002, p. 192).

The diffusion tradition has classified people, in terms of demographics, in explaining the variables that influence the adoption of an innovation. For that reason, some scholars often criticize that this theory may not provide a causal explanation of why and how people adopt certain technologies. Nevertheless, when it comes to the use and choice of old and new media, diffusion theory will be suited for explaining why some people prefer to use the old media or new media, because this theory provides some conceptual guidance for understanding the adoption of some technologies or innovations. According to evolution of media technology, interpersonal influences or channels are important even though in the past the individual is usually the unit of analysis. Also, critical mass becomes an important factor in adopting new media because new media are interactive tools and thus are required to many users for getting efficiency. That is, the more people use, the more people get benefits. Markus (1987) proposed that the value of an interactive communication medium is associated with the number of other users. For example, in the case of the mp3, a social influence such as peer pressure that interacts with young generation needs to be cool or to gain status drives young people to adopt the mp3 as an innovation. Besides, when it comes to the emergence of interactive communication such as the new communication technologies, Rogers (1996) mentioned, “a critical mass occurs when the diffusion process becomes self-sustaining. After the critical mass point, individuals in a system perceive that “everybody else” has adopted the interactive innovation. With each successive adopter of an interactive innovation, the new idea becomes more valuable not only for each future adopter, but also for each previous adopter” (p. 418-419). When it comes to the future of diffusion theory, we expect that the popularity of diffusion research will increase because as in recent years, new communication technologies have increased and proliferated.

Diffusion study and Two-Step Flow study
According to Lowery and Defleur (1995), since diffusion study emphasizes the role of interpersonal communications, the diffusion study by Ryan and Gross “parallels what was independently found by Lazarsfeld and his associates in the discovery of the two-step flow process in the very different setting of The People’s Choice” (p. 132). "The People’s Choice” showed that audiences are not powerless and passive. The study showed that interpersonal channels, such as opinion leaders, are more important than the mass media. Unlike magic bullet theory, both of these studies emphasized the role of the opinion leaders and interpersonal communication, such as face-to-face interactions influencing decision-making.


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Bartending/Mixers/Tonic water

Tonic water is a carbonated mixer containing quinine. It is carbonated water flavored like a bitter lemon or lime, with a little sugar.

Tonic water generally is marked on a soda gun with a 'Q'; and in bottles by a yellow label. This is different from plain soda water, which is under 'S', or in a bottle with a blue label.

An interesting trait of tonic water is that quinine is fluorescent. By using a black light, you can make the liquid glow; your bar setup may be interestingly enhanced by stocking extra tonic water in clear bottles at strategic locations, and using a blacklight to produce the interesting glow. A clear-top bar with fluorescent tube blacklights run under it would also make certain drinks glow.

title: Bartending/Mixers/Tonic water


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Radiation Oncology/Treatment planning/Motion

Tumor and Organ At Risk Motion

Abdominal Tumors

 * PMID 15817361, 2005 — "The correlation between internal and external markers for abdominal tumors: implications for respiratory gating." Gierga BP et al. Int J Radiat Oncol Biol Phys. 2005 Apr 1;61(5):1551-8.
 * 4 pts. liver tumors.
 * PMID 15050340, 2004 — "Quantification of respiration-induced abdominal tumor motion and its impact on IMRT dose distributions." Gierga BP et al. Int J Radiat Oncol Biol Phys. 2004 Apr 1;58(5):1584-95.
 * Used surgical clips and fluroscopy. 7 pts (6 pancreas, 1 liver).
 * Average peak-to-peak motion (i.e., twice the amplitude): LR < 2mm, CC 7.4mm, AP 3.8mm
 * IMRT plan using PTV margin of 8 mm (accounting for tumor motion only, not setup inaccuracy)

Abdominal Organs

 * Pittsburgh; 2006 PMID 16690437 -- "Abdominal organ motion measured using 4D CT." (Brandner ED, Int J Radiat Oncol Biol Phys. 2006 Jun 1;65(2):554-60.)
 * 4D CT scanning, 13 patients
 * sup-inf organ motion: liver 1.3 cm, spleen 1.3 cm, left kidney 1.1 cm, right kidney 1.3 cm
 * Conclusion: 4D CT can accurately measure abdominal organ motion throughout respiration


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User:SimRPGman

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Consciousness Studies/The Philosophical Problem/Appendixt

Home

Dynamics: Velocities in a Four Dimensional Universe
Many students of consciousness studies are unaware of the modern derivations of physical theories. Nowhere is this more evident than in the belief that Newtonian Physics is a complete description of physics. However, this belief is incorrect, the concept of Kinetic Energy that underlies Newtonian Dynamics is due to relativistic mass increases as a result of the existence of a four dimensional universe and the invariance of physical laws. The mass increase, although a relativistic effect, is noticeable as kinetic energy because it is equivalent to an energy of $$E=mc^2$$ where the speed of light squared is a huge number. What we call classical physics is in fact relativistic physics. (See special relativity for beginners for an introduction). Contrary to popular belief our observation must be described using four interrelated coordinate axes, not three.

Relativistic transformation of velocity
If time and space are affected by the four dimensional nature of the universe then velocity, which is the ratio of distance travelled to time taken, should also be affected. In the simplest case, where Bill and Jim are travelling towards each other they both obtain the same value for the velocity of approach. This is because Bill and Jim are symmetrical, either can consider either to be moving. The symmetry disappears however if both Bill and Jim are observing an object moving relative to both of them. Suppose there is an object moving at v relative to Jim and Jim is moving at J relative to Bill, what is the velocity of the object relative to Bill?

The illustration above shows that time dilation and phase are going to be involved in the comparison of Bill and Jim's estimate of the velocity of the moving object. If B is Bill's estimate of the velocity and J is Jim's estimate then, for an object moving along the x axis:

B = (J + v)/(1 + Jv/c2)

Derivation:

 * From the Lorentz transformation equations:

 * Distance travelled by object as observed by Jim = (x-vt)/√(1-v2/c2)

 * Time taken observed by Jim = (t - (v/c2)x)/ √ (1-v2/c2)

 * Where x and t are distance and time observed by Bill.

 * Velocity observed by Jim is distance/time: J = (x-vt) / (t - (v/c2)x)

 * Therefore x-vt = J (t - v/c2x)

 * So x/t, the velocity measured by Bill is: B = (J + v)/(1 + Jv/c2)

The equation given above only applies to observers moving in the directions shown. The involvement of time dilation and the fact that an object that is stationary for one observer will be moving for the other means that even velocities at right angles to the direction at which Jim and Bill approach each other will be affected (although a different equation must be applied).

Conservation of Momentum in a 4D Coordinate System
The conservation of momentum is a basic empirical law of Newtonian physics. It states that the products of the masses and velocities of a set of particles is constant. The way that Bill and Jim record different velocities for the same objects around them means that the Newtonian conservation of momentum law does not apply and is only an empirical approximation for low velocities. Most importantly, if Newtonian momentum is conserved for one observer it is not conserved for another observer moving relative to the first. Einstein originally formulated Relativity Theory using an axiom that the laws of physics are the same for all observers and amended the conservation of momentum law so that it applied in a 4D universe. Modern physics relies on Noether's Theorem:

To every symmetry corresponds a conservation law. Conversely, for every conservation law there is a corresponding type of symmetry.

The symmetrical nature of translations in space implies conservation of linear momentum.

Rotational symmetry implies conservation of angular momentum.

Time symmetry implies conservation of energy.

Invariance with respect to gauge transformations implies conservation of electric charge. Momentum is the product of mass and velocity. If Newtonian momentum, where mass is a constant, is not conserved because the velocity is variable between observers then perhaps the mass changes to compensate for the velocity. If conservation of momentum is expressed as:

Mass(1) x Velocity(1) = Mass(2) x Velocity(2)

Then it can be shown that the conservation equation is true if:

Mass(2) = Mass(1)/√(1-u2/c2)

Where u is the speed of the object, not the velocity.

In general the mass, m, of an object travelling at speed, u, is:

m = m0/√ (1-u2/c2)

Where m0 is the mass of the object when it is at rest relative to the observer.

In other words, the momentum of an object is conserved but its mass is variable. The variation of mass with speed is a direct consequence of translational symmetry and the existence of a four dimensional universe. This variation in mass with speed is easy to demonstrate in relatively simple particle accelerators because even at half the speed of light the mass is 1.15 times the rest mass.

The new form of the conservation of momentum law suggests that the Newtonian formula for force must be replaced. Force is rate of change of momentum, in Newtonian physics this is the product of a constant mass times a change in velocity (acceleration). In 4D physics this must be calculated in terms of both the change in velocity and the change in mass.

Force = d(m0u/√(1-u2/c2))dt

Where u is velocity and u is speed.

The kinetic energy of a particle accelerated from rest to velocity u is:

K = ∫ F dx

But F = d(mu)/dt

K = ∫ d(mu)/dt dx

K = ∫ d(mu) dx/dt

dx/dt = u

K = ∫ (mdu + udm) u

K = ∫ (mudu + u2dm)

In the discussion of momentum above it was shown that the mass of a moving object is related to its mass at rest by:

m = m0/√ (1-u2/c2) This can be rewritten as : m2c2 - m2u2 = m02c2

Taking differentials:

2mc2dm - m22udu - u22mdm = 0

Dividing by 2m:

mu du + u2 dm = c2 dm

But:

K = ∫ (mudu + u2dm)

Therefore, integrating between mass at rest and mass at u:

K = ∫ c2 dm = c2 (m-m0)

So :

Kinetic energy = mc2 - m0c2

The kinetic energy is present as the extra mass due to motion.

Total energy = m0c2 + Kinetic energy = mc2

The rest mass energy is given by:

E = m0c2

A result that is amply demonstrated in atomic bombs where the mass of uranium is greater than the mass of the products generated by fission (cesium and rubidium). The excess mass being converted into a cataclysmic release of energy.

The Binomial Expansion of (1 - v2/c2)-1/2

The binomial theorem can be used to expand any expression of the form (a + x )n so, (1 - v2/c2)-1/2 can be expanded by substituting 1 for a and - v2/c2 for x.

(a + x )n = an + nan-1x + n(n-1)/2! nan-2x2 + ...

therefore:

(1 - v2/c2)-1/2 = 1 + 1/2 v2/c2 + (-1/2)(-3/2)/2! v4/c4 + ...

(1 - v2/c2)-1/2 = 1 + 1/2 v2/c2 + 3/8 v4/c4 + 5/16 v6/c6 ...

If the velocity is small compared with the speed of light the terms from 3/16 v4/c4 onwards become negligible so:

(1 - v2/c2)-1/2 ≈ 1 + 1/2 v2/c2

The Newtonian Approximation for Kinetic Energy
The kinetic energy of the particle (the energy due to motion) is:

KE = mvc2 - m0c2 But it was seen earlier that mv = m0(1 - v2/c2)-1/2

So:

KE = m0(1 - v2/c2)-1/2 c2 - m0c2

KE = m0c2 ((1 - v2/c2)-1/2 - 1)

But (1 - v2/c2)-1/2 ≈ 1 + 1/2 v2/c2

So

KE ≈ m0v2 /2

Which is the Newtonian empirical approximation for kinetic energy. Notice that the full result is derived from symmetries in a 4D universe whereas the Newtonian result is derived from empirical formulae.

Electricity and Magnetism in a 4D Universe
One of the greatest achievements of Relativity Theory was to unify electricity and magnetism. These two effects can be seen to be the same phenomena observed in different ways. This is shown in the illustration below.

It can be seen that once the idea of space-time is understood the unification of the two fields is straightforward. Jim is moving relative to the wire at the same speed as the negatively charged current carriers so Jim only experiences an electric field. Bill is stationary relative to the wire and observes the electrostatic attraction between Jim and the current carriers as a magnetic field. Bill observes that the charges in the wire are balanced whereas Jim observes an imbalance of charge.

Incidently, the drift velocity of electrons in a wire is about a millimetre per second but the electrons move at about a million metres a second between collisions (See link below).

Useful links:

http://hyperphysics.phy-astr.gsu.edu/hbase/electric/ohmmic.html">http://hyperphysics.phy-astr.gsu.edu/hbase/electric/ohmmic.html

http://hyperphysics.phy-astr.gsu.edu/hbase/relativ/releng.html">http://hyperphysics.phy-astr.gsu.edu/hbase/relativ/releng.html