Teensy-weensy, itsy-bitsy

I want to put a few things in perspective. Strings, for instance.

As I mentioned last time, I’m working my way through George Musser’s The Complete Idiot’s Guide to String Theory. I want to get a handle on what subatomic level we are dealing with when we talk about strings.

Deconstruction of matter:

1. Macroscopic, e.g., diamonds

2. Molecular, diamond allotrope

3. Atomic, carbon

4. Subatomic - Electron

5. Subatomic - Quarks

6. Strings (Image**)

First, let’s take another look at the diagram I used in my last entry, showing the progressively smaller and more basic parts of matter.

Now, try to wrap your mind around this concept: the most common estimate of the size of strings is that a string compares to an atom in roughly the same proportion that a human being compares to the entire observable universe. And we know that atoms are so small that it is only in recent years that we’ve been able to scan to the level of individual atoms with advanced electron microscopes. So I find it hard to imagine how infinitely smaller strings must be.

Beyond that basic fact lies the practical problem of ever even being able to observe a string—assuming they do exist. It would be tantamount to looking from earth to some very, very distant planet in a galaxy far, far away with the intention of being able to read the scoreboard at a Buckyball stadium there (Buckyball being the sporting pastime of the residents of that very, very distant planet). It’s likely to be a long time, if ever, that we have instruments able to directly observe either strings or Buckyball scoreboards on distant planets.

Of course, even when I was in school, no one had ever seen an atom. Technically, just a few short decades ago, atoms were just a theory, sort of like strings are now—or global warming or evolution, for that matter. But, even then, there was evidence that atoms existed. Their effects could be predicted and tested so that, even if we couldn’t see them, we knew the little devils were there.

We’re not quite at that point with string theory, though. There are competing theories which still have legitimate physicist adherents. Among the major contenders is loop quantum gravity theory. Among other things, the loop gravity theory proposes that space itself is actually composed of something, “space atoms” if you will, that act as the means for the transference of gravity—gravity being the main problem between defining the macro-universe (planets, stars, galaxies) and the micro-universe (atoms, protons, neutrons, electrons quarks and strings).

While the effects of gravity were well established by folks like Isaac Newton and Albert Einstein, their theories don’t hold up on that micro-universe, subatomic level. Hence, as I’ve mentioned, quantum theory was developed.

As Musser notes, for most practical purposes, those discrepancies don’t matter. Both astronomers and particle physicists can each explore their respective fields without regard to the theoretical offsets regarding gravity. But, eventually, when the ultimate questions of black holes or the Big Bang must be answered, then it will matter a great deal.

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What would you do if I sang of a string?

Would you stand up and walk out on me?

At Amazon.com

For the next week or few, I suspect we’ll be talking about string theory. I’ve just started a new book, The Complete Idiot’s Guide to String Theory by George Musser (2008, the Penguin Group, New York, NY).

This week, I just want to go over the basics, some of which I’ve discussed before.

Back in the day, when I studied science in school, the theory was that the basic building blocks of matter were atoms, and atoms were composed of protons, electrons and neutrons, held together by various electro-magnetic, inertial and gravitational forces. This is, more or less, the classical theory of physics, fully supported by the general theory of relativity.

But there was a, shall we say, “companion” theory of physics called quantum mechanics; however, when I was in school, it was not popular enough to make it into the general science textbooks. Even so, quantum mechanics was a serious field of study limited only by the problem that many of its theories could not be tested given the technology of the day.

Over time, though, technology began to catch up and quantum theories became more and more accepted.

Deconstruction of matter:
1. Macroscopic, e.g., diamonds
2. Molecular, diamond allotrope
3. Atomic, carbon
4. Subatomic - Electron
5. Subatomic - Quarks
6. Strings       (Image**)

The problem remains, however, that some of the basic tenets of quantum theory and classical theory, while provable, are not, apparently, compatible. This led to a quest for a “unified theory” that would explain those incongruent notions. String theory is the most popular hypothesis to date, though it is neither complete nor unanimously acclaimed. String theory is based on the work of Italian theoretical physicist Gabriele Veneziano and was first described in 1969.

Very, very simply, string theory proposes that the atomic particles we called protons, electrons and neutrons are made up of even smaller stuff and that this stuff is in the form of both looped and open-ended one-dimensional strings. It is the nature and behavior of these strings which, so to speak, ties together quantum theory and classical (general relativity) theory.

Then it gets interesting.

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Round 'em up, head 'em out

Time for snowbirds to gather and get the flock out'a here. Adios, Arizona; howdy, Colorado. So, for the next few weeks or more, we'll be giving this a rest.

Superconductors

A superconductor.

Actually, I’ll be writing about superconductivity today, but superconductors made a better title, and also allowed me to use a clever graphic—lest we forget that these blogs are mostly about keeping me amused.

First, let’s have a couple demonstrations showing what superconductivity is all about.

Demonstration 1. Wave your hand about in the air as rapidly as you can. Now, move your hand just as rapidly, but keeping your palm in firm contact with the surface of a carpet. (Hey, I said firm contact.)

Okay, don’t be bleeding all over the carpet. So, do you feel the heat on your palm? That heat is caused by friction with the surface of the carpet as it resists the movement of your hand, what one might call (and I am calling) resistance.

Demonstration 2. For this demonstration you will need your mother’s permission: pop a slice of bread in your toaster (an English muffin would be better). Now crank that handle down. (It’s plugged in, right?) Hold your horses, give it a few seconds.

Image**

Now very carefully—don’t get too close—look down into the toaster slot. (If your eyebrows are smoldering, you’re too close.) See those glowing wires aligned on either side of the muffin? Those wires are made of a metal alloy designed to resist the flow of electricity. That resistance to the electricity causes them to heat up, glow red and yellow, and hence the delicious carmelization of the surface of the English muffin.

Now pop out that muffin, slather on a generous portion of margarine or butter (see how it puddles deliciously in all the nooks and crannies?), add a healthy dollop of jam, jelly or honey, and enjoy. In quantum mechanics, this is referred to as a snack.

The wires in the toaster conduct electricity. (Starting to see where we’re headed, eh?) They’re just designed to conduct it poorly, so there is resistance, which causes heat, with some light as a byproduct. The same method is used to create light in an incandescent light bulb—which is also why they’re inefficient, because so much of the electricity ends up creating heat rather than light.

On the other hand, most electric lines or wires are designed to conduct electricity with as little resistance as possible, from the cord connecting your computer to your house current to the high voltage transmission lines that carry electricity from generating facilities to distribution and transformer stations throughout the country.

There are two problems, however. First, all metal wires—and there really aren’t any other kind in general use at present—have some resistance to electric flow. Secondly, the lower the voltage of that flow, the more susceptible it is to resistance.

So, to carry electricity over distances, power companies raise the voltage to very high—and more dangerous—levels. Even so, it’s estimated that upward of 5% of the power generated in this country is lost to resistance before it even makes it to a consumer’s electric meter. To transmit power at preferred lower voltages would result in exponentially higher losses.

At the opposite end of the spectrum, the flow of electricity in the ever-smaller circuits of computers causes problems of speed, proximity and heat that have our current technologies reaching their theoretical limits.

What physicists have sought, ever since electricity became more than just a conjurer’s trick, was a means to conduct electricity at low voltages without loss to resistance.

Image: American Superconductor

In 1911, Dutch physicist (and Noble laureate) Heike Kamerlingh Onnes, who studied how materials behaved at very low temperatures, discovered that, when super-cooled—and by super-cooled I mean temperatures very close to absolute zero, -459.67 degrees Fahrenheit—some materials lost all resistance to electrical conductivity. Hence the term, superconductors.

In theory, if one put an electrical current into a closed loop of superconductive material, the electrical current would move unimpeded, without any loss, through that loop indefinitely.

Image: ItsSaulConnected.com

The problem remains, even 100 years later, that materials still must be super-cooled to become superconductors, an expensive and impractical consideration for general use. But research has been developing materials that can superconduct at slightly warmer temperatures and the holy grail is that material that can superconduct within ambient temperatures.

And I wouldn’t mind finding some way to toast my English muffins faster.

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Out on a limb: Time out

(Continued from last week.)

Consider how casually we treat time. For instance, in this country, most of us, twice a year (daylight savings time, eh?), up and change it just to suit our convenience. This has the effect of a makeover—one 23-hour day and one 25-hour day every year. And we think little of it.

Then there’s the matter of time zones. We divide the earth into 24 zones, to account for the 24 hours of its rotation (but how do we speed it up or slow it down to accommodate the 23- and 25-hour days?). Being round, the earth accounts for the 360 degrees of a circle. Dividing those 360 degrees by 24 hours gives us 15 degrees of longitude for each time zone.

Time warp? Time wrap?

Except, of course, where it’s not convenient for us. As an example, consider the gerryman- dering of the time line (see the inset map) along the borders of Washington, Oregon, Nevada, Utah, Idaho and Montana.

Or we can time travel simply by moving about on the earth’s surface. On the continental USA we can change our time by as much as three hours. I’ve often wondered what might happen if one were crossing a time zone boundary precisely at the stroke of midnight. Do you travel through time by an entire day? Or might you slip into a rift in the fabric of time itself, reappearing in another dimension exactly like our own so that you would be unaware of the dimensional shift—but would you then be destined for an entirely different future? Maybe it’s already happened.

To cease belaboring the point: we really don’t take time all that seriously.

Stomping our collective foot, we whine, “But we do take time seriously! What about the saying, ‘Time is money’?"

Seriously? Is time money? Or is effort money? Or one’s determination and response? If time were money, might not we all be rich?

Taking this back to the realm of physics…well, let’s save that for next time.

To be continued. Sometime.

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