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Dismantling Space and Time [Review of book by Brian Greene]
Tech Central Station ^ | 09 March 2004 | Kenneth Silber

Posted on 07/15/2004 7:52:36 AM PDT by PatrickHenry

Space and time are pervasive in our everyday experience, and yet it is hard to say exactly what they are. They resist definition in terms other than themselves. Moreover, they have various subtle and elusive properties, with which science continues to grapple. Relativity and quantum mechanics, the physics breakthroughs of the 20th century, revolutionized scientific thinking about these subjects. And this revolution has not played itself out, since cutting-edge physics today involves further radical rethinking of time and space.

The Fabric of the Cosmos: Space, Time, and the Texture of Reality, by Brian Greene (Knopf, $28.95), is an excellent guide to the science of space and time, and to modern physics more generally. The book provides lucid expositions of arcane topics that often are either oversimplified or obfuscated in physics popularizations. Greene is adept at placing complex ideas into context, explaining how they relate to each other and distinguishing the various degrees between well-established fact and wild speculation.

Greene, a Columbia University professor, has emerged as a high-profile expositor of physics in recent years. Indeed, he is a physicist with a certain cultural cachet; among other activities, he has hosted a documentary based on his previous book The Elegant Universe, performed a cameo role in the movie Frequency, and collaborated with the Emerson String Quartet on a project combining superstring theory with string music.

Is space "something" -- a physical entity -- or just a concept for describing relations among objects? Greene sorts through several centuries of thought about this question. In the late 1600s, Isaac Newton argued that space has an absolute, independent existence, while his rival Gottfried Wilhelm von Leibniz took the relationist view. In the 19th century, physicist Ernst Mach undermined the prevailing Newtonian position, setting motion against a backdrop not of absolute space but of widely distributed matter. The forces we feel when we spin or accelerate, Mach argued, are exerted on us by all the other objects near and far; if you were alone in the cosmos, you wouldn't feel a thing.

Then came Einstein, whose relativity theories both reaffirmed and refuted aspects of the relationist view. It became clear that Newton's absolute space does not exist; space and time depend on the relative motion of observers. Then again, space was evidently "something," since it could be curved and warped by matter and energy. Moreover, spacetime, the union of what were previously seen as distinct entities, was absolute. In Greene's analogy, spacetime is like a loaf of bread; it can be sliced different ways by observers at different locations, but the overall shape is independent and unchanging.

Quantum mechanics transformed science's understanding of matter and energy, and brought new implications for space and time. There was now seen to be genuine randomness in physical phenomena, unlike the deterministic laws of Newton and Einstein. Particles exist in a haze of probability, and interfere with one another like waves. Moreover, space no longer reliably performs its basic role of separating objects. Rather, particles can be "entangled," or correlated with each other over large distances even though nothing passes between them; they behave, in a sense, as one object. Such entanglement is a very difficult concept to explain, and Greene does a laudable job of it.

Time presents further puzzles. For one, does time "flow"? Physics provides no clear basis for our sense of a shifting present that is distinct from past and future. Indeed, relativity runs counter to that everyday perception, since observers at widely different locations and speeds will disagree on what is happening "now." Greene leans toward the view that time's flow is a function of the human mind rather than of fundamental physics. But he notes, sensibly, that our understanding of this matter may be far from complete.

The arrow of time, or direction in which things change, poses another question. We are accustomed to eggs scrambling but not unscrambling, and to black coffee and cream being stirred into light coffee but never the reverse. Yet at a more fundamental level, physics appears symmetrical between past and future; a movie of the particles that compose the egg or coffee could be run in reverse and you wouldn't know the difference.

The time asymmetry of everyday life arises from increasing entropy, a measure of the disorder in a system. But what explains the drive toward higher entropy? A plausible answer is provided by the cosmological theory of inflation, in which space underwent a phase of extremely rapid expansion. Remarkably, as Greene points out, understanding why eggs get scrambled requires consideration of the earliest moments of the universe.

Yet science's picture of the early universe (and of certain cosmic features such as black holes) remains fuzzy. The reason is that the relevant theories, quantum mechanics and general relativity, are incompatible with each other. General relativity posits a spacetime that is geometrically smooth. Quantum mechanics suggests spacetime, at the smallest scale, is wildly tumultuous. Hence, physicists search for a theory that will reconcile such differences. This was the impetus for superstring theory, which later morphed into M-theory (the M can stand for various things, including mystery, matrix, and membrane).

The superstring/M-theory approach raises the possibility that the familiar three dimensions of space (and one dimension of time) are not all there is to reality. Instead, there are higher dimensions, which go unnoticed because they are curled up at small scales or impervious to the electromagnetic radiation with which we normally see things. In fact, space as we know it may be a "something" that is as real as any object: a three-dimensional membrane, or "brane," embedded in a higher-dimensional spacetime.

Research continues on M-theory, and on a competing approach called loop quantum gravity (which can be understood, roughly speaking, as involving little loops of space). Experimental verification of such cutting-edge physics is difficult, but Greene expresses optimism that experiments in the not-distant future will provide a window into the nature of space and time. There are indications in current theory that space and time arise from something yet more fundamental -- but what that something is, nobody knows.


TOPICS: Culture/Society; Miscellaneous; Philosophy
KEYWORDS: briangreene; cosmology; crevolist; physics; space; stringtheory; time
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Space, time, relativity, Mach's Principle, quantum mechanics, branes ... oodles of subjects to mull over.
1 posted on 07/15/2004 7:52:37 AM PDT by PatrickHenry
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To: VadeRetro; jennyp; Junior; longshadow; RadioAstronomer; Physicist; LogicWings; Doctor Stochastic; ..
Science list Ping! This is an elite subset of the Evolution list.
See the list's description in my freeper homepage. Then FReepmail me to be added or dropped.
2 posted on 07/15/2004 7:53:45 AM PDT by PatrickHenry (#26,303, registered since the 20th Century, never suspended, over 186 threads posted.)
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To: PatrickHenry

I'm reading this book now - its very good.


3 posted on 07/15/2004 7:56:13 AM PDT by linear
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To: linear

I have some other stuff to read ahead of this one, but it just bumped to the head of the queue.


4 posted on 07/15/2004 8:00:21 AM PDT by Gefreiter ("Ignorance is king. Many would not prosper by its abdication.")
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To: linear

Would I need an advanced degree in physics to understand the book? I must admit that I had a difficult time understanding alot of Hawking's book.


5 posted on 07/15/2004 8:02:55 AM PDT by Shryke (Never retreat. Never explain. Get it done and let them howl.)
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To: PatrickHenry
...understanding why eggs get scrambled requires consideration of the earliest moments of the universe.

So ultimately, the grand unified theories might be tested by their ability to explain the most ordinary of events?

6 posted on 07/15/2004 8:04:03 AM PDT by js1138 (In a minute there is time, for decisions and revisions which a minute will reverse. J Forbes Kerry)
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To: js1138
So ultimately, the grand unified theories might be tested by their ability to explain the most ordinary of events?

I think that is a damned good way to start, don't you?

7 posted on 07/15/2004 8:08:34 AM PDT by Shryke (Never retreat. Never explain. Get it done and let them howl.)
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To: Shryke

Universe in a Nutshell is an easier read than A Brief History of Time, if you want to go the Hawking route. I find Greene's writing much more engaging than Hawking's. I think you'll do fine with Greene. I'm a lawyer (generally defined as an engineer with math anxiety) and I'm managing to wade through it. Don't bother trying to keep up with the footnotes though. Here there be dragons. lol.


8 posted on 07/15/2004 8:10:49 AM PDT by linear
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To: linear

Good, thanks. Me hate things make me feel like dumbhead.


9 posted on 07/15/2004 8:12:36 AM PDT by Shryke (Never retreat. Never explain. Get it done and let them howl.)
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To: PatrickHenry

I just started reading this. So far, it's excellent.


10 posted on 07/15/2004 8:12:54 AM PDT by Constitution Day
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To: js1138

It all depends on what level you examine it. There are some wonderful and mysterious things going on in them there eggs. Personally I prefer mine over easy, with enchiladas beneath.


11 posted on 07/15/2004 8:13:22 AM PDT by linear
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To: linear

This thread has got me interested in the book. Quite an cool topic.


12 posted on 07/15/2004 8:14:58 AM PDT by MDspinboyredux
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To: Shryke

One of the things that Brian Greene is known for is his ability to write about this stuff in way that non-physicists can grasp it.

His show on PBS "The Elegant Universe" was amazingly easy to follow.


13 posted on 07/15/2004 8:15:51 AM PDT by krb (the statement on the other side of this tagline is false)
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To: PatrickHenry

I find this fascinating, and have some thoughts on the subject(s) myself.

Unfortunately, I have neither the space nor time to expound on these matters now. :o)

OK....I hear the groans from here! But I couldn't help myself!!! :o)


14 posted on 07/15/2004 8:16:56 AM PDT by Rhetorical pi2
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To: linear

I could take some comfort in a theory that explained dust bunnies, and why I can't fix overcooked food by putting it back in the fridge for a while.


15 posted on 07/15/2004 8:18:27 AM PDT by js1138 (In a minute there is time, for decisions and revisions which a minute will reverse. J Forbes Kerry)
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To: MDspinboyredux

I agree, it is fantastic stuff.

I wish there was a way to express things on paper in a 3-dimensional manner. It would make some of the illustrations a tad easier to follow. It must not be easy to mass-produce holograms. lol.


16 posted on 07/15/2004 8:18:47 AM PDT by linear
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To: MDspinboyredux

I agree, it is fantastic stuff.

I wish there was a way to express things on paper in a 3-dimensional manner. It would make some of the illustrations a tad easier to follow. It must not be easy to mass-produce holograms. lol.


17 posted on 07/15/2004 8:18:50 AM PDT by linear
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To: PatrickHenry

Thanks for the ping!


18 posted on 07/15/2004 8:19:46 AM PDT by Alamo-Girl
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To: js1138

I don't have a theory, but if you decrease your cooking time and increase your dust-bunny hunting time, perhaps then your universe will be in sync. ;-)


19 posted on 07/15/2004 8:22:33 AM PDT by linear
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To: linear

Heh-heh. I agree. What I'd like to see is a video produced by Greene that has him explaining his theories.

I've always thought that the arguement that time was a mental construct was interesting. Although I'm of the opinion that time is the waste product of entropy (sorta like heat is the by-product of rapid oxidation).

Time 'happens'.


20 posted on 07/15/2004 8:27:39 AM PDT by MDspinboyredux
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To: MDspinboyredux

That's a cool idea.

I've always favored the notion that time is a combination of more than one dimension. However, I'm content to know that time itself will tell what the correct answer is. lol


21 posted on 07/15/2004 8:34:16 AM PDT by linear
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To: PatrickHenry
it's all about matter. One of the properties of matter is its intrinsic motion. The fact of matter, given its intrinsic (and extrinsic) motion, yields, in and of itself, certain byproducts. The most notable of these are time and space. Without matter (and motion), you would have neither. Without matter in motion, "time" could not exist, since it is a spinoff of matter in motion, and nothing more. Without matter in motion, "space" would not exist, since space is nothing more than the distance between materials. Without matter, indeed, "space" would be nothingness, which we are unable to say much about, because the instant that we do, "somethingness" erupts.
22 posted on 07/15/2004 8:42:26 AM PDT by Migraine
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To: linear

I'm with you! All this pondering makes me hungry. (Santa Fe style)


23 posted on 07/15/2004 8:48:06 AM PDT by OSHA (The meek may inherit the earth but they'll never get out of the Wal-Mart parking lot.)
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To: PatrickHenry; OSHA; Darksheare; Fedora; The Scourge of Yazid

Dismantling Space is easy. Putting it back together without having a bunch of parts still laying around is hard.

I once rebuilt a 65 Ford Fairlane. When I was through I still had a lot of parts so I built a Harley.


24 posted on 07/15/2004 8:57:31 AM PDT by Conspiracy Guy (Kerry has a Carter Plan. Bush has a Reagan Plan. You choose which is your plan.)
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To: linear

I agree that time is multi-dimentional. Migrane actually hits is in a couple of posts above this one.

Since matter is multi-dimentional, then its by-products (time) are also multi-dimentional.

Migrane also beat me to an interesting mind exercise. If you are to believe that space is non-material (just 'distance' between stuff), without matter would time exist? To expand on this, knowing time is relative to position, if we just pop you into this nothingness, without any other matter(and therefore no relative position) would you age?


25 posted on 07/15/2004 8:58:42 AM PDT by MDspinboyredux
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To: OSHA

I hear you. My salsa verde count must be getting low.


26 posted on 07/15/2004 8:58:54 AM PDT by linear
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To: OSHA
Niels Bohr:

Big deal! Has mister smarty pants had a play written about him yet? Don't think so! Pfft! "String theory" my German exile ass!

27 posted on 07/15/2004 9:00:31 AM PDT by The Scourge of Yazid ("I've had Shut up Stew before, and it sure as didley didn't taste like that!")
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To: PatrickHenry

BTTT


28 posted on 07/15/2004 9:06:29 AM PDT by facedown (Armed in the Heartland)
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To: Conspiracy Guy

Putting the first two dimensions back together isn't too bad, it's when I get to the third dimension that I can never find the right size screwdriver.


29 posted on 07/15/2004 9:14:20 AM PDT by Fedora (Kerryman, Kerryman, does whatever a ketchup can/Spins a lie, any size, catches wives just like flies)
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To: Fedora

Heh-heh


30 posted on 07/15/2004 9:18:36 AM PDT by MDspinboyredux
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To: Fedora

# 2 Philips left hand grip. Don't forget the Metric Crescent Wrench.


31 posted on 07/15/2004 9:21:13 AM PDT by Conspiracy Guy (Kerry has a Carter Plan. Bush has a Reagan Plan. You choose which is your plan.)
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To: Fedora
OSHA's Crackpot theory o' the day:

Space exists only because matter exists. Gravity is nothing more than "surface tension" of space trying to minimize itself.

Time travel was invented 50 years ago but is being suppressed by a consortium of time travelers from the future. (or the past depending on your reference point).

32 posted on 07/15/2004 9:23:30 AM PDT by OSHA (The meek may inherit the earth but they'll never get out of the Wal-Mart parking lot.)
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To: Migraine

I'm with you. It fits well with my thoughts on gravity espressed (in the first part) of #32.


33 posted on 07/15/2004 9:27:16 AM PDT by OSHA (The meek may inherit the earth but they'll never get out of the Wal-Mart parking lot.)
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To: OSHA; Darksheare
This is true. Darksheare and I are part of the consortium. But I will go back a few minutes and not post this so you will never know.
34 posted on 07/15/2004 9:28:54 AM PDT by Conspiracy Guy (Kerry has a Carter Plan. Bush has a Reagan Plan. You choose which is your plan.)
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To: The Scourge of Yazid

I have a "string theory" too....hmmmm...better not.


35 posted on 07/15/2004 9:31:10 AM PDT by OSHA (The meek may inherit the earth but they'll never get out of the Wal-Mart parking lot.)
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To: Migraine
One of the properties of matter is its intrinsic motion

Do not confuse matter with body. Watch our for the Higgs field--the modern aether. Make no absolute statements. Hahahaha.

36 posted on 07/15/2004 9:35:26 AM PDT by RightWhale (Withdraw from the 1967 UN Outer Space Treaty and establish property rights)
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To: Conspiracy Guy

"# 2 Philips left hand grip. Don't forget the Metric Crescent Wrench."

Hey, that works--thanks! Now if I could just get the dang flashlight to shine so that I can see the fourth coordinate. . .


37 posted on 07/15/2004 9:41:26 AM PDT by Fedora (Kerryman, Kerryman, does whatever a ketchup can/Spins a lie, any size, catches wives just like flies)
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To: Fedora

The flashlight will not work until you are finished. Please hurry I need to go to the men's room.


38 posted on 07/15/2004 9:44:28 AM PDT by Conspiracy Guy (Kerry has a Carter Plan. Bush has a Reagan Plan. You choose which is your plan.)
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To: RightWhale; The Scourge of Yazid; OSHA; Darksheare

That is an interesting hypothesis, but how does the string theory fit into all of this?


39 posted on 07/15/2004 9:46:58 AM PDT by scott0347 ("Free Republic": Disturb, manipulate, demonstrate for the right thing)
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To: OSHA; Darksheare

"OSHA's Crackpot theory o' the day:"
"Space exists only because matter exists."

Being a crackpot I'd agree with this. It follows logically from the definitions of matter and space.

"Gravity is nothing more than "surface tension" of space trying to minimize itself."

I've thought of something like that, but am not sure how to express it in precise logical/mathematical terms or verify it yet.

"Time travel was invented 50 years ago but is being suppressed by a consortium of time travelers from the future. (or the past depending on your reference point)."

That'd be BSIC, the consortium led by Darksheare and I. We also suppress the location of all the erasers to all the golf-club pencils in the world.


40 posted on 07/15/2004 9:49:31 AM PDT by Fedora (Kerryman, Kerryman, does whatever a ketchup can/Spins a lie, any size, catches wives just like flies)
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To: Conspiracy Guy

"The flashlight will not work until you are finished. Please hurry I need to go to the men's room."

Not sure you wanna do that just yet, what with space warping in weird curved directions and all. . .


41 posted on 07/15/2004 9:50:36 AM PDT by Fedora (Kerryman, Kerryman, does whatever a ketchup can/Spins a lie, any size, catches wives just like flies)
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To: Fedora

I know that is why I said hurry!!!!


42 posted on 07/15/2004 9:56:29 AM PDT by Conspiracy Guy (Kerry has a Carter Plan. Bush has a Reagan Plan. You choose which is your plan.)
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To: Fedora

The surface tension theory also splains the speed limit C. The faster you go the greater the resistance.


43 posted on 07/15/2004 9:56:42 AM PDT by OSHA (The meek may inherit the earth but they'll never get out of the Wal-Mart parking lot.)
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To: Fedora

Too much coffeeeeeeeeeeeee..........!!!!!!!!


44 posted on 07/15/2004 9:56:49 AM PDT by Conspiracy Guy (Kerry has a Carter Plan. Bush has a Reagan Plan. You choose which is your plan.)
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To: Fedora

Never mind to late.


45 posted on 07/15/2004 9:57:04 AM PDT by Conspiracy Guy (Kerry has a Carter Plan. Bush has a Reagan Plan. You choose which is your plan.)
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To: King Prout

We are playing over here.


46 posted on 07/15/2004 9:59:13 AM PDT by OSHA (The meek may inherit the earth but they'll never get out of the Wal-Mart parking lot.)
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To: linear
I saw him speak on C-span..............I'm not much into physics and quantum theories, but this guy had me enthralled.

The broken egg explanation was good...

47 posted on 07/15/2004 10:02:36 AM PDT by OXENinFLA
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To: OSHA

oh. oops.


48 posted on 07/15/2004 10:02:46 AM PDT by King Prout (Viggo Bozodozeus is your friend... Viggo Bozodozeus deserves all trust... submit to Viggo Bozodozeus)
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To: PatrickHenry; OSHA

oh, yes... "entanglement"

I heard something on this subject last week.

interesting property. If it could be harnessed, instantaneous communications irrespective of range would become possible.


49 posted on 07/15/2004 10:07:19 AM PDT by King Prout (Viggo Bozodozeus is your friend... Viggo Bozodozeus deserves all trust... submit to Viggo Bozodozeus)
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To: linear
I wish there was a way to express things on paper in a 3-dimensional manner.

I'm also reading this book (just got to the m-theory part), and visualizing these concepts is extremely difficult. When he talks about adjacent 3-branes, even a 3-D illustration wouldn't help.

I was interested in his description of the "Higgs ocean" being the embodiment of the effect we call "inertia." I had not see that particular concept anywhere before.

But this book has a marked soporific effect -- I can't read more than 20 pages without falling asleep!

50 posted on 07/15/2004 10:08:42 AM PDT by forsnax5 (The greatest problem in communication is the illusion that it has taken place.)
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