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<h2 class="first-section-title"><a name="652"></a><a name="ch06lev1sec3"></a>Closing Thoughts</h2><p class="first-para">In 1965, an Intel Corporation co-founder named Gordon Moore suggested that the number of transistors in a processor would double every 18 months. This rule of thumb became known as <i class="emphasis">Moore's Law</i>. Moore's Law implies that the linear dimensions of a transistor are cut in half every three years (see <a class="internaljump" href="#ch06fig03">Figure 6.3</a>).</p>
<div class="figure">
<a name="653"></a><a name="ch06fig03"></a><span class="figuremediaobject"><a href="images/fig379%5F01%5F0%2Ejpg" NAME="IMG_99" target="_parent"><img src="images/fig379_01.jpg" height="98" width="272" alt="Click To expand" border="0"></a></span>
<br style="line-height: 1">
<span class="figure-title"><span class="figure-titlelabel">Figure 6.3</span></span>
</div>
<p class="para">A micrometer is one-millionth of a meter:</p>
<p class="para">1 <span class="unicode">μ</span>m = 10<sup>-6</sup>m</p>
<p class="para">The anthrax bacterium is 1 to 6 micrometers in length. A human hair is 100 micrometers in diameter. Most chips today have transistors that possess sub-micron dimensions.</p>
<p class="para">A nanometer is one-thousandth of a micrometer:</p>
<p class="para">1 nm = 10<sup>-9</sup>m</p>
<p class="para">= 1/1000 <span class="unicode">μ</span>m</p>
<p class="para">The diameter of a hydrogen atom, in its ground state, is roughly one-tenth of a nanometer.</p>
<p class="para">Solid-state physicists will tell you that an electron needs a path of about three atoms wide to move from one point to another. If the <a name="654"></a><a name="IDX-352"></a>path width gets any smaller, quantum mechanics takes hold and the electron stops behaving in a predictable manner.</p>
<p class="para">In 1989, Intel released the 80486 processor. The 80486 had transistors whose linear dimensions were 1 micrometer. Using 1989 as a starting point, let's see how long Moore's Law will last before it hits the three-atom barrier.</p>
<a name="655"></a><a name="ch06table02"></a>
<table class="table" border="1">
<caption class="table-title">
<span class="table-title"><span class="table-titlelabel">Table 6.2</span></span>
</caption>
<thead>
<tr valign="top">
<th class="th" scope="col" align="left">
<p class="table-para">
<b class="bold">Year</b>
</p>
</th><th class="th" scope="col" align="left">
<p class="table-para">
<b class="bold">Size</b>
</p>
</th><th class="th" scope="col" align="left">
<p class="table-para">
<b class="bold">Processor</b>
</p>
</th>
</tr>
</thead>
<tbody>
<tr valign="top">
<td class="td" align="left">
<p class="table-para">1989</p>
</td><td class="td" align="left">
<p class="table-para">1 micrometer</p>
</td><td class="td" align="left">
<p class="table-para">Intel 80486 (1 micrometer)</p>
</td>
</tr>
<tr valign="top">
<td class="td" align="left">
<p class="table-para">1992</p>
</td><td class="td" align="left">
<p class="table-para">0.5</p>
</td><td class="td" align="left"> </td>
</tr>
<tr valign="top">
<td class="td" align="left">
<p class="table-para">1995</p>
</td><td class="td" align="left">
<p class="table-para">0.25</p>
</td><td class="td" align="left">
<p class="table-para">Pentium Pro (.35 micrometers)</p>
</td>
</tr>
<tr valign="top">
<td class="td" align="left">
<p class="table-para">1998</p>
</td><td class="td" align="left">
<p class="table-para">0.125</p>
</td><td class="td" align="left"> </td>
</tr>
<tr valign="top">
<td class="td" align="left">
<p class="table-para">2001</p>
</td><td class="td" align="left">
<p class="table-para">0.0625</p>
</td><td class="td" align="left">
<p class="table-para">Pentium 4 (.18 micrometers)</p>
</td>
</tr>
<tr valign="top">
<td class="td" align="left">
<p class="table-para">2004</p>
</td><td class="td" align="left">
<p class="table-para">0.03125</p>
</td><td class="td" align="left"> </td>
</tr>
<tr valign="top">
<td class="td" align="left">
<p class="table-para">2007</p>
</td><td class="td" align="left">
<p class="table-para">0.015625</p>
</td><td class="td" align="left"> </td>
</tr>
<tr valign="top">
<td class="td" align="left">
<p class="table-para">2010</p>
</td><td class="td" align="left">
<p class="table-para">0.0078125</p>
</td><td class="td" align="left"> </td>
</tr>
<tr valign="top">
<td class="td" align="left">
<p class="table-para">2013</p>
</td><td class="td" align="left">
<p class="table-para">0.00390625</p>
</td><td class="td" align="left"> </td>
</tr>
<tr valign="top">
<td class="td" align="left">
<p class="table-para">2016</p>
</td><td class="td" align="left">
<p class="table-para">0.001953125</p>
</td><td class="td" align="left"> </td>
</tr>
<tr valign="top">
<td class="td" align="left">
<p class="table-para">2019</p>
</td><td class="td" align="left">
<p class="table-para">0.000976563</p>
</td><td class="td" align="left"> </td>
</tr>
<tr valign="top">
<td class="td" align="left">
<p class="table-para">2022</p>
</td><td class="td" align="left">
<p class="table-para">0.000488281</p>
</td><td class="td" align="left"> </td>
</tr>
</tbody>
</table>
<p class="para">According to Moore's Law, the length of a transistor will be about 4.88x10<sup>-10</sup> meters by the year 2022. This corresponds to a path width that is roughly four hydrogen atoms across. As you can see from the third column, Intel has made valiant attempts at trying to keep up. However, nobody has really been able to sustain the pace set by Moore's Law. In 2001, Moore's Law says that we should have had transistors whose design rule was .06 micrometers. In 2001, Intel's top-of-the-line Pentium 4 had a design rule of .18 micrometers. Vendors that say they are staying abreast of Moore's Law are really cheating by making their chips larger. This tactic increases the total number of transistors, but it doesn't increase the transistor density per unit length.</p>
<p class="para">Once the wall is hit, there is really nothing that we will be able to do (short of changing the laws of physics) to shrink transistors. The only way to increase the number of transistors in a processor will be to make the processor larger. The party will be over for the processor manufacturers. Hardware people will no longer be able to have their cake and eat it too. Businesses that want to increase the horsepower of their information systems may have to revert back to room-sized computers.</p>
<p class="para">In the beginning, algorithms and the people who worked with them were valued highly because the hardware of the day was often <a name="656"></a><a name="IDX-353"></a>inadequate for the problems that it faced. Take the Bendix G-15, for example, which had 2,160 words of magnetic drum memory in 1961. In order to squeeze every drop of performance out of a machine, you needed to be able to make efficient use of limited resources. Program size was typically the biggest concern. If instructions existed in more than one spot, they were consolidated into a procedure. This meant that the execution path of a task tended to spend a lot of time jumping around memory. I remember two Control Data engineers telling me about how they simulated an entire power grid in southern California using less than 16KB of memory.</p>
<table border="0" cellspacing="0" cellpadding="0" class="note">
<tr>
<td valign="top" class="admon-check"></td><td valign="top" class="admon-title">Note </td><td valign="top" class="admon-body">
<p class="first-para">In 2002, with the advent of 256MB SDRAM chips and 512KB L2 caches, program size is not such a pressing concern. Program speed is the new focal issue. This has led to an inversion of programming techniques. Instead of placing each snippet of redundant code in its own function, developers have begun to deliberately insert redundant instructions. For example, inline functions can be used to avoid the overhead of setting up an activation record and jumping to another section of code.</p>
</td>
</tr>
</table>
<p class="para">When Moore's Law meets the laws of physics, the computer industry will once again be forced to look for better solutions that are purely software-based, primarily because all the other alternatives will be more expensive. One positive result of this is that the necessity to improve performance will drive the discovery of superior algorithms. Computer science researchers may see a new heyday.</p>
<p class="para">The demise of Moore's Law may also herald the arrival of less desirable developments. Lest you forget, major technical advances, such as radar and nuclear energy, were first put to use as weapons of war. Potential abuse of technology has already surfaced, even in this decade. At Super Bowl XXXV, hundreds of people involuntarily took part in a virtual lineup performed by Face Recognition Software. Is there a reason why people who wish to watch a football game need to be treated like suspects in a criminal case? Why was the public only informed about the use of this software after the game had occurred?</p>
<p class="para">This is just the beginning. Artificial intelligence programs will eventually be just as sophisticated and creative as humans. To a certain extent, they already are. In 1997, an IBM RS/6000 box named Deep Blue conquered the world chess champion, Garry Kasparov, in a six-game tournament. I was there when it happened (well, sort of). I was huddled with an Intel 80486 the afternoon of the final game, reading a "live" transcript of the match via an IBM Java applet. For a more graphic example of AI progress, try playing <a name="657"></a><a name="IDX-354"></a>against the bots of Id Software's Quake 3. You would be impressed with how wily and human those bots seem.</p>
<p class="para">As the capabilities of hardware and software ramp upward, the surveillance that we saw at the Super Bowl will give way to something more insidious: behavior prediction and modification. The credit bureaus and various other quasi-governmental agencies already collect volumes of data on you. Imagine all of this data being fed into a computer that could consolidate and condense the information into some kind of elaborate behavioral matrix. If you can simulate someone's behavior, you can make statistical inferences about their future behavior. Furthermore, if you can predict what someone is going to do, you can also pre-empt their behavior in an effort to control them. There could be software built that less-than-scrupulous leaders could use to implement social engineering on a national scale. Indoctrination does not have to assume the overt façade that Huxley or Bradbury depicted. It can be streamed in sub-liminally through a number of seemingly innocuous channels.</p>
<blockquote class="blockquote">
<p class="first-para">"We are the middle children of history, raised by television to believe that someday we'll be millionaires and movie stars and rock stars, but we won't."</p>
<p class="last-para">— Tyler Durden</p>
</blockquote>
<p class="para">As time passes, these kinds of issues will present themselves. It is our responsibility to identify them and take constructive action. The problem with this is that the capacity to recognize manipulation does not seem, to me, to be a highly valued trait. The ability to think independently is not something that I was taught in high school. If anything, most public schools present a sanitized version of <i class="emphasis">civic education</i>. Not that this matters much, but most people don't start asking questions until the world stops making sense.</p>
<p class="para">Nevertheless, if we sit idle while the thought police install their telescreens, we may end up like Charles Forbin, slaves to a massive and well-hidden machine.</p>
<blockquote class="blockquote">
<p class="first-para">"In time, you will come to regard me with not only awe and respect, but love."</p>
<p class="last-para">— Colossus, speaking to Charles Forbin in <I>Colossus: The Forbin Project</I> (1969)</p>
</blockquote>
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