The Universe
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Guardian
Member # 2476
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written Saturday, March 19 2005 11:15
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Someone gave a link in a similar discussion long ago. Here it is: The Official String Theory Web Site -------------------- Polaris Posts: 1828 | Registered: Saturday, January 11 2003 08:00 |
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Law Bringer
Member # 335
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written Saturday, March 19 2005 11:18
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Hawking is a theoretical physicist. That means he deals mostly with pure mathematics, but they just happen to be mathematics related to how the universe works. A good working definition of space would be distance between points. When everything is in a singularity, everything is one point. Put another way, the distance between all points is zero. That's not even one-dimensional space. —Alorael, who doesn't think energy exerts gravitational force. E=mc^2 is a conversion equation, but one cannot exert a force on an energy with no mass and thus Newton's third law would be violated. However, it's quite possible that non-Newtonian physics allow for forces acting on energy. Where are the local physicists? Posts: 14579 | Registered: Saturday, December 1 2001 08:00 |
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For Carnage, Apply Within
Member # 95
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written Saturday, March 19 2005 11:58
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Energy does indeed exert gravitational force equal to what it would if it were converted to mass, and the two are in many ways the same thing. However, since it takes a great deal of energy to equate to a small amount of mass, and gravity itself is a fairly weak force, the gravitational influence of energy on a system is usually miniscule. EDIT: A good example is a black hole. Its gravity prevents light (and other massless particles) from escaping, even though light has no mass. (Keep in mind, however, that I'm by no means an expert here. If the real physicists would pick up that'd be nice.) [ Saturday, March 19, 2005 12:03: Message edited by: Turumby ] Posts: 567 | Registered: Friday, October 5 2001 07:00 |
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BANNED
Member # 4
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written Saturday, March 19 2005 13:17
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(And if you want to be PC, they're "melanin-endowed minority" holes.) -------------------- 人 た ち を 燃 え る た め に 俺 は か れ ら に 火 を 上 げ る か ら 死 ん だ Posts: 6936 | Registered: Tuesday, September 18 2001 07:00 |
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Agent
Member # 3364
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written Sunday, March 20 2005 11:56
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My head hurts... Have these 'virtual' particles themselves ever been observed? It seems that the whole theory of exploding black holes rests singularly on the exsistance of particles that appear at random out of nowhere. -------------------- "Even the worst Terror from Hell can be transformed to a testimony from Heaven!" - Rev. David Wood 6\23\05 "Do all the good you can, by all the means you can, in all the ways you can, in all the places you can, at all the times you can, to all the people you can, as long as you ever can." - John Wesley Posts: 1001 | Registered: Tuesday, August 19 2003 07:00 |
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Shock Trooper
Member # 4214
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written Sunday, March 20 2005 11:57
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quote:Einstein violated one of Newtons laws, proving that his laws aren't trustworthy. quote:I've learned that there are four forms of energy: Light, matter, movement and warmth. However, light, as Einstein proved, consists of particles. Thus, light is, indirectly, equal to matter. Warmth is the vibration of molecules, and thus is, indirectly, movement. Am I wrong? Posts: 356 | Registered: Tuesday, April 6 2004 07:00 |
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Triad Mage
Member # 7
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written Sunday, March 20 2005 12:08
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Yes. You are very wrong. -------------------- "At times discretion should be thrown aside, and with the foolish we should play the fool." - Menander ==== Drakefyre's Demesne - Happy Happy Joy Joy desperance.net - We're Everywhere ==== You can take my Mac when you pry my cold, dead fingers off the mouse! Posts: 9436 | Registered: Wednesday, September 19 2001 07:00 |
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Bob's Big Date
Member # 3151
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written Sunday, March 20 2005 12:51
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There are two things in the universe: matter and energy. They are made of the same particles, just in different configurations. Light is matter and energy; temperature is energy, and movement is a vector. And not all of Newton's laws were correct. Einstein's generally hold up in the laboratory. -------------------- The biggest, the baddest, and the fattest. Posts: 2367 | Registered: Friday, June 27 2003 07:00 |
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For Carnage, Apply Within
Member # 95
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written Monday, March 21 2005 00:16
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Dreams: I'm pretty sure virtual particles have been observed. If not, they must rest on some very sound theory, because the books I read on the subject take their existence for granted. Alec: It's not really true that Newton's laws were "incorrect," just that they are not perfectly precise, and that imprecision happens to grow to a noticeable amount at extremely high velocities. Einstein's theories just have a better (thought still not perfect) precision. Posts: 567 | Registered: Friday, October 5 2001 07:00 |
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...b10010b...
Member # 869
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written Monday, March 21 2005 00:39
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quote:I'm pretty sure the fact that they haven't been observed and probably can't be is part of the reason why they're called virtual particles. It's just that they make awfully convenient physical models -- a particle under the influence of electromagnetic forces really does behave as if it were interacting with photons, even though those photons are virtual and unobserved. [ Monday, March 21, 2005 00:39: Message edited by: Thuryl ] -------------------- My BoE Page Bandwagons are fun! Roots Hunted! Posts: 9973 | Registered: Saturday, March 30 2002 08:00 |
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Shock Trooper
Member # 4214
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written Monday, March 21 2005 03:32
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quote:I was expecting this answer, but was also expecting an explanation. Posts: 356 | Registered: Tuesday, April 6 2004 07:00 |
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...b10010b...
Member # 869
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written Monday, March 21 2005 03:47
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Okay, here's a start. There are a whole *bunch* of different forms of energy. Kinetic energy (movement). Thermal energy (heat). Chemical, gravitational, mechanical and electrical potential energy. Nuclear energy. There are probably a few more I haven't thought of. -------------------- My BoE Page Bandwagons are fun! Roots Hunted! Posts: 9973 | Registered: Saturday, March 30 2002 08:00 |
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Shock Trooper
Member # 4214
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written Monday, March 21 2005 04:14
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quote:Nuclear energy is chemical energy, which is equal to matter. I mentioned thermal and kinetic energy, and gravity is, accommodating to a book I read, a dimension, not an energy-form. Please forgive me if my words are incorrect. [ Monday, March 21, 2005 04:16: Message edited by: Mind ] Posts: 356 | Registered: Tuesday, April 6 2004 07:00 |
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Shock Trooper
Member # 3898
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written Monday, March 21 2005 04:19
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There's also the fact that light, and all it's wavelengths (eg. radio waves, microwaves), is not made up of particles - not exactly. It's made up of weird particle-waves that act like particles some of the time and waves the others. As are almost all other subatomic particles (any contradictions?). I have my own opinion on the multiple universe/creation of the universe theory. It involves black holes, multidimensional bending, and time as either an infinite loop or just infinite in all directions. It's rather strange, and I doubt it would hold up to criticism, but it is what I currently believe in, as it seems at least as sound as any other, and if anyone asks, I suppose I'll air it. -------------------- ~Note : The professional newbie's advice should not be taken seriously, or at all.~ LINKAGE Posts: 364 | Registered: Saturday, January 17 2004 08:00 |
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For Carnage, Apply Within
Member # 95
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written Monday, March 21 2005 04:23
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Gravity is a force, and all forces are the product of some sort of energy. The force that makes two masses attract each other can't really be classified as chemical, thermal, etc., hence the seperate category. As for the rest, your division of energy into those four categories is pretty arbitrary. Chemical and nuclear energy are pretty different in terms of their sources and effects, and the former is not "equivalent to matter" at all. The criterion for scientific classifications like this is not so much "is it correct?" as "is it useful?", and saying that all energy is one of four functionally equivalent things just causes more confusion than it settles. Posts: 567 | Registered: Friday, October 5 2001 07:00 |
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Infiltrator
Member # 4637
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written Monday, March 21 2005 04:24
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Space theories are very falible, as they are mainly pure speculation over little real knowledge. Science, to be science, requires experimentation. But we do not have the means to do so, except through long distance observation, some sampling from near planets (Venus and Mars) and much speculation. If the famous "What is true today might be false tomorrow" is right, this science branch fits completely this sentence. :) Just out of curiosity, check out 13 things that don't make sense, most of them, you'll see, are Space problems. new scientist web page -------------------- Visit the Blades of Avernum Center and the Beta Testing Center -------------- "Beware lest anyone cheat you through philosophy and empty deceit, according to the tradition of men, according to the basic principles of the world, and not according to Christ." Colossians 2:6-9 Posts: 483 | Registered: Tuesday, June 29 2004 07:00 |
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Shock Trooper
Member # 4214
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written Monday, March 21 2005 05:04
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quote:Gravity is both the weakest of the universe's four main forces and a dimension. "Matter bends space", claimed Einstein. quote:Five. I forgot to mention electrical energy. I appreciate your euphemism. I was expecting a very arrogant and offensive answer to my nonsensical and preposterous words. Posts: 356 | Registered: Tuesday, April 6 2004 07:00 |
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Shock Trooper
Member # 3898
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written Monday, March 21 2005 05:41
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Gravity is not in fact a dimension. I find the best way of explaining this is the rubber sheet analogy. Take a sheet of rubber, streched out like a trampoline. Place a few metal balls on it, and notice that the rubber, which was previously flat, two-dimensional, bends in a third dimension, due to the depression made when you place the rubber ball. The third dimension is not gravity, but the affects of the rubber sheet bending into the third dimension are. Now, apply it to a three-dimensional universe (the rubber sheet), with planets as the metal balls. [ Monday, March 21, 2005 05:41: Message edited by: Model of a Modern Major Specific ] -------------------- ~Note : The professional newbie's advice should not be taken seriously, or at all.~ LINKAGE Posts: 364 | Registered: Saturday, January 17 2004 08:00 |
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Shock Trooper
Member # 4214
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written Monday, March 21 2005 06:27
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If you are right, I was misinformed. Perhaps I should just stop discussing this subject and silently read the other replies. I've bothered you with my false and nonsensical words enough already. Posts: 356 | Registered: Tuesday, April 6 2004 07:00 |
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For Carnage, Apply Within
Member # 95
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written Monday, March 21 2005 08:15
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Nah, you should ask questions and get people to explain the things that don't make sense. This is confusing stuff, and takes a while to grasp. Posts: 567 | Registered: Friday, October 5 2001 07:00 |
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Shock Trooper
Member # 4214
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written Monday, March 21 2005 08:36
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Damn the education system for learning me false information! Not only is it inadequate and purposeless, but also nonsensical. I've found an interesting site concerning the energy-forms, which contradicts everything we said about it. [ Monday, March 21, 2005 08:44: Message edited by: Mind ] Posts: 356 | Registered: Tuesday, April 6 2004 07:00 |
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Law Bringer
Member # 335
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written Monday, March 21 2005 09:25
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Not exactly. It says that energy is energy is energy, except for potential energy, which may become energy at some future point. This is true, but that doesn't make it useful. Just because thermal energy is the movement of very small particles and kinetic energy could be defined loosely as movement does not make them equivalent. in all respects. On some level they are the same, but on others (notably macroscopically) it's much easier to say that one block is moving quickly and another is very hot. Those clearly don't mean the same things. The site can say there is one form of energy and be correct, but that doesn't make it useless to talk about many forms of energy. Using various equations (e.g. E=mv^2) would be difficult otherwise. Ranking energies or forces in terms of strength also doesn't quite make sense. On a subatomic level, nuclear forces are extremely powerful. On a slightly larger scale, electric forces hold everything together. Zoom out even farther and magnetism takes effect, and then gravity. (This is not scientific at all, but it is true-ish if you don't dig too hard.) I have trouble seeing gravity as the weakest force when it's the one swinging planets around. —Alorael, who has two more things to add. The first is that virtual particles may be unprovable but useful as a hypothesis. Think Occam's Razor. The second is that Newton's laws aren't exactly correct, but they tend to hold true and be easier to use at low speeds and large scales. "Everyday" physics can be Newtonian and correct to a degree past which nobody cares. Newton just happened to be very, very wrong in other circumstances. Posts: 14579 | Registered: Saturday, December 1 2001 08:00 |
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Shock Trooper
Member # 4214
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written Monday, March 21 2005 09:40
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Sigh. The most popular Dutch dictionary cannot translate the word "kernkracht" to English. According to the book "Stephen Hawkings Universe", gravity is the weakest of the four main forces of the Universe. The other three are the electromagnetic force, and two I can't translate to English. Posts: 356 | Registered: Tuesday, April 6 2004 07:00 |
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Off With Their Heads
Member # 4045
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written Monday, March 21 2005 09:56
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The other two forces (and they are called in English the "fundamental forces" usually) are just called the "strong force" and the "weak force." You might as well go and get a textbook on this sort of stuff. It seems like you have half of a grasp of most of this, and you just need to read about it a little bit more to figure it out. -------------------- Arancaytar: Every time you ask people to compare TM and Kel, you endanger the poor, fluffy kittens. Kelandon's Pink and Pretty Page!!: the authorized location for all things by me The Archive of all released BoE scenarios ever Posts: 7968 | Registered: Saturday, February 28 2004 08:00 |
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Shock Trooper
Member # 4214
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written Monday, March 21 2005 10:00
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Literally translated to English, the Dutch terms for these fundamental forces are "the weak coreforce" and "the strong coreforce". Who do you consider to know much about the universe? [ Monday, March 21, 2005 10:04: Message edited by: Mind ] Posts: 356 | Registered: Tuesday, April 6 2004 07:00 |