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The First Atom (Page 2)
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Shaddim
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Nov 11, 2004, 12:46 AM
 
Originally posted by mikellanes:
One thought, When discussing the "first atom", or the creation of the universe the concept of God is not necessary. There is no question about the universe to which the answer is "God" that could not then be posed about God. E.g.:

-If God caused the universe to exist, then God was either caused by something else, or uncaused entirely. If God can be uncaused entirely, so can the universe.
-If God designed the universe, then God was either designed by something else, or not designed at all. If God can be ordered without design, so can the universe.
I think it's more like, "Henry Ford designed the car, but did the car understand Henry Ford?" No. Why? Cars can't think, and neither can we, at least not on the level of "something" that could put into motion all you see around you.
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mikellanes
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Nov 11, 2004, 01:03 AM
 
Originally posted by MacNStein:
Cars can't think, and neither can we, at least not on the level of "something" that could put into motion all you see around you.
Edit:

How about: We live in a world that obeys the laws of physics, the starting point (infinite nothingness) didn't need to obey the laws of physics, thus we can not understand the starting point.

A deity does not need to be involved, even in your argument.
( Last edited by mikellanes; Nov 11, 2004 at 01:12 AM. )
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Wiskedjak
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Nov 11, 2004, 01:12 AM
 
Originally posted by MacNStein:
Light actually is matter, since energy is simply substance in a state of transition (I think that's how it goes).
What is matter?
http://dictionary.reference.com/search?q=matter&r=67
Something that occupies space and can be perceived by one or more senses; a physical body, a physical substance, or the universe as a whole.

Something that has mass and exists as a solid, liquid, gas, or plasma.
Light does not occupy space.
Light does not have mass and does not exist as a solid, liquid, gas or plasma.
http://math.ucr.edu/home/baez/physic...ight_mass.html
( Last edited by Wiskedjak; Nov 11, 2004 at 01:21 AM. )
     
mikellanes
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Nov 11, 2004, 01:20 AM
 
Originally posted by Wiskedjak:
What is matter?
This is "stuff" which can or cannot be seen directly. Dark Matter, Not Dark Matter.

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Nov 11, 2004, 06:34 AM
 
Originally posted by mikellanes:
From what I have studied recently, time is always around, whether we observe it or not.
I think we need to forget time.
We created time, based on our revolutions around the sun. Is it really universal? The universe doesn't care about our revolutions around the sun, we're just one of eleventy-billion planets orbiting a star at some random interval.

What happens when we take time out of our equations?
     
mikellanes
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Nov 11, 2004, 08:53 AM
 
Originally posted by AKcrab:
I think we need to forget time.
We created time, based on our revolutions around the sun. Is it really universal? The universe doesn't care about our revolutions around the sun, we're just one of eleventy-billion planets orbiting a star at some random interval.

What happens when we take time out of our equations?
Good Morning!!

Hmm interesting, what does happen when we take time out of the equation? Not much Id say, it is relative, which is why we measure it in a relative way.

I do think time is universal, at least in our universe, everything that happens takes time, you can define time in many different ways but the fact that getting up and walking to the shower (that is what I am about to do) can not be instantaneous is in itself the reality of time. IMO.
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Shaddim
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Nov 11, 2004, 10:31 AM
 
Originally posted by Wiskedjak:
What is matter?

Light does not occupy space.
Light does not have mass and does not exist as a solid, liquid, gas or plasma.
http://math.ucr.edu/home/baez/physic...ight_mass.html
and people wonder why Scientiists and Philosophers can't usually get along? *sigh*

From your article:
This question comes up in the context of wondering whether photons are really "massless," since, after all, they have nonzero energy and energy is equivalent to mass according to Einstein's equation E=mc2._ The problem is simply that people are using two different definitions of mass._ The overwhelming consensus among physicists today is to say that photons are massless._ However, it is possible to assign a "relativistic mass" to a photon which depends upon its wavelength._ This is based upon an old usage of the word "mass" which, though not strictly wrong, is not used much today._ See also the Faq article Does mass change with velocity?.

Thus, photons do have some type of relative mass.
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badidea
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Nov 11, 2004, 10:58 AM
 
Originally posted by mikellanes:
Good Morning!!

Hmm interesting, what does happen when we take time out of the equation? Not much Id say, it is relative, which is why we measure it in a relative way.

I do think time is universal, at least in our universe, everything that happens takes time, you can define time in many different ways but the fact that getting up and walking to the shower (that is what I am about to do) can not be instantaneous is in itself the reality of time. IMO.
If you take time out of the equations then there is NO instantaneous because this would need the existance of time!!

It's really hard to understand because all our life is based on time but as soon as you manage to keep it out of your theories, many things are a lot easier to explain!
Take the "Big Boom" for example. Let's say it is true (like in the beginning of this thread). I always had huge problems with that theory because I could never understand why something should be a small tiny little something for millions/billions/trillions/endless years and suddenly it would make BOOM.......if there's no time on the other hand...
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Dakar
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Nov 11, 2004, 11:01 AM
 
Originally posted by Wiskedjak:
Light does not have mass
That not entirely correct. If light didn't have mass, then the gravity of a black hole wouldn't affect it.

But then again, our understanding of gravity is so poor its pathetic.
     
Shaddim
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Nov 11, 2004, 11:22 AM
 
Originally posted by badidea:
If you take time out of the equations then there is NO instantaneous because this would need the existance of time!!

It's really hard to understand because all our life is based on time but as soon as you manage to keep it out of your theories, many things are a lot easier to explain!
Take the "Big Boom" for example. Let's say it is true (like in the beginning of this thread). I always had huge problems with that theory because I could never understand why something should be a small tiny little something for millions/billions/trillions/endless years and suddenly it would make BOOM.......if there's no time on the other hand...
That's why I like the "Cyclical Universe" theory. I don't believe that it stayed in that state for any length of "time" at all, but that it crunched to a single point, that achieved absolute mass (or close to it), and then exploded again. Think of the universe as a huge heart, each beat of that "heart" is an expansion and a contraction (over the span of 50-80 billion years). This would also go along with some rather unusual verses from the Talmud namely: "For it is said that Elohim created and destroyed many worlds before this one was made" and "this is not a world unending, but a cycle of creation and destruction". I've always found those verses to be fascinating.
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badidea
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Nov 11, 2004, 11:25 AM
 
Originally posted by MacNStein:
That's why I like the "Cyclical Universe" theory. I don't believe that it stayed in that state for any length of "time" at all, but that it crunched to a single point, that achieved absolute mass (or close to it), and then exploded again. Think of the universe as a huge heart, each beat of that "heart" is an expansion and a contraction (over the span of 50-80 billion years). This would also go along with some rather unusual verses from the Talmud namely: "For it is said that Elohim created and destroyed many worlds before this one was made" and "For this is not a world unending, but a cycle of creation and destruction". I've always found those verses to be fascinating.
Yep, this theory also sounds good to me!
(time is still a human invention though)
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Shaddim
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Nov 11, 2004, 11:28 AM
 
Originally posted by badidea:
Yep, this theory also sounds good to me!
(time is still a human invention though)
I know... but we need reference points to discuss things.
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Dakar
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Nov 11, 2004, 11:28 AM
 
Originally posted by MacNStein:
That's why I like the "Cyclical Universe" theory.
I'm fond of it too, as its a nice dodge to the "Who created the Bing Bang question, though it basically solves the problem with the paradox of always having existed, which I find personally reminiscent of lessons on God's existence.
     
mikellanes
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Nov 11, 2004, 11:56 AM
 
Originally posted by MacNStein:
That's why I like the "Cyclical Universe" theory. I don't believe that it stayed in that state for any length of "time" at all, but that it crunched to a single point, that achieved absolute mass (or close to it), and then exploded again. Think of the universe as a huge heart, each beat of that "heart" is an expansion and a contraction (over the span of 50-80 billion years).
Good post, I tend to agree, not that that makes the theory any more "right"

Good points as well badidea
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mikellanes
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Nov 11, 2004, 11:59 AM
 
Originally posted by Dakar:
though it basically solves the problem with the paradox of always having existed, which I find personally reminiscent of lessons on God's existence.
How does it solve that? I don't think it is even trying to achieve that goal.
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mikellanes
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Nov 11, 2004, 12:02 PM
 
Originally posted by badidea:
I always had huge problems with that theory because I could never understand why something should be a small tiny little something for millions/billions/trillions/endless years and suddenly it would make BOOM.......if there's no time on the other hand...
I would say there was time, it just didn't need to obey the laws of time therefore no time. Does that make any sense? LOL
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Dakar
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Nov 11, 2004, 12:09 PM
 
Originally posted by mikellanes:
How does it solve that? I don't think it is even trying to achieve that goal.
I'm saying it solves the problem of creation of the universe by creating a paradox.

I'm definitely not thinking (or typing) clearly today.
     
Shaddim
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Nov 11, 2004, 12:10 PM
 
Originally posted by Dakar:
I'm saying it solves the problem of creation of the universe by creating a paradox.
Meaning it never truly "began", but has always been in this cycle (thus the paradox).
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Wiskedjak
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Nov 11, 2004, 01:00 PM
 
Originally posted by MacNStein:
and people wonder why Scientiists and Philosophers can't usually get along? *sigh*

From your article:
This question comes up in the context of wondering whether photons are really "massless," since, after all, they have nonzero energy and energy is equivalent to mass according to Einstein's equation E=mc2._ The problem is simply that people are using two different definitions of mass._ The overwhelming consensus among physicists today is to say that photons are massless._ However, it is possible to assign a "relativistic mass" to a photon which depends upon its wavelength._ This is based upon an old usage of the word "mass" which, though not strictly wrong, is not used much today._ See also the Faq article Does mass change with velocity?.

Thus, photons do have some type of relative mass.
Also from my article:
Sometimes people like to say that the photon does have mass because a photon has energy E = hf where h is Planck's constant and f is the frequency of the photon._ Energy, they say, is equivalent to mass according to Einstein's famous formula E = mc2._ They also say that a photon has momentum and momentum is related to mass p = mv._ What they are talking about is "relativistic mass", an outdated concept which is best avoided
...
Sometimes people ask "If light has no mass how can it be deflected by the gravity of a star?" One answer is that any particles such as photons of light, move along geodesics in general relativity and the path they follow is independent of their mass._ The deflection of star-light by the sun was first measured by Arthur Eddington in 1919._ The result was consistent with the predictions of general relativity and inconsistent with the Newtonian theory._ Another answer is that the light has energy and momentum which couples to gravity._ The energy-momentum 4-vector of a particle, rather than its mass, is the gravitational analogue of electric charge._ The corresponding analogue of electric current is the energy-momentum stress tensor which appears in the gravitational field equations of general relativity._ A massless particle can have energy E and momentum p because mass is related to these by the equation m2 = E2/c4 - p2/c2which is zero for a photon because E = pc for massless radiation._ The energy and momentum of light also generates curvature of space-time so according to theory it can attract objects gravitationally._ This effect is far too weak to have been measured._ The gravitational effect of photons does not have any cosmological effects either (except perhaps in the first instant after the big bang)._


All we've really proven here is that sometimes light exhibits characteristics of matter and sometimes characteristics something that does not meet the definitions of matter. CreepingDeath seems to think that matter must be created by an outside force that is not matter which did not have to be created. According to CD, things that are not matter do not have to be created. There are things which exist in our universe that exhibit characteristics which are not consistent with matter.

All I'm trying to get to is this; how does CreepingDeath know that things that aren't matter don't have to be created if, in his own words, "everything has to come from somewhere"?
     
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Nov 11, 2004, 02:16 PM
 
Originally posted by mikellanes:
Very interesting post, what is your background if you don't mind me asking.
It should be enough to say that I'm a physicist. I admit that my understanding of the big bang theory may not be entirely right, and may not be universally accepted, but every talk on the subject I've attended has insisted that the big bang is the expansion of space itself. Because of the equivalency of space and time in relativity, that means that such would also have to be the beginning of time, too.

Read here and here for more info.

From what I have studied recently, time is always around, whether we observe it or not.
To think that the universe just came out of nothing like that would require something like the external impulse of God.
That's more of a philosophical argument than a physical one. As I said, causality is a temporal concept, so asking what caused the universe to be is nonsense unless you can invalidate relativity's equivalence of time and space (good luck). Instead, you should ask, "What exists outside of the universe," at which point you are firmly outside of scientific territory.

I think the older BB theory is nothing more than a secular creation myth.
Let me know what you think about: http://www.marxist.com/science/bigbang.html

I am interested in your opinion.
Perhaps it was at first. The problem, though, is that there's a mountain of evidence to back it up by now: the maximum age of stars and globular clusters, red shift of galaxies, background radiation, etc. So, regardless of the motives of those who cooked it up, it is a testable scientific theory that has survived many tests. If you want to shoot it down, find some test that it can, and does, fail. Not just some test of philosophical reasoning, but some physical measurement. That or propose a falsifiable theory that explains of the data better, more simply, or that explains more data. It is absolutely critical that the theory be falsifiable by some physical measurement or else it's not a scientific theory.

"POSTREMO NEMO AEGROTUS QUIDQUAM SOMNIAT TAM INFANDUM, QUOD NON ALIQUIS DICAT PHILOSOPHUS." --Varro, Fragmenta ("No madman has ever dreamed up anything so weird that some philosopher will not say it.")

BlackGriffen
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BlackGriffen
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Nov 11, 2004, 02:26 PM
 
Originally posted by Dakar:
That not entirely correct. If light didn't have mass, then the gravity of a black hole wouldn't affect it.

But then again, our understanding of gravity is so poor its pathetic.
No, light has zero rest mass. The thing is that gravity doesn't couple to mass, it couples to energy. Photons definitely have energy, and thus are affected by gravity.

That is the most commonly used definition of matter, I think: anything that has a rest mass.

Here is the equation for the energy of any particle (like an electron or photon) in relativity:

E = sqrt((m*c^2)^2 + (p*c)^2)

where: m = rest mass, c = speed of light, p = momentum, E = energy

So, to find out if something is matter, you use a lower and lower momentum example of it and find out how much energy is left over. Thing is, photons disappear entirely as their momentum goes to zero.

Much of the rest mass of a proton or nucleus, for instance, actually comes from the potential energy of the quarks bound up in them and not from the constituent quarks themselves. This is why the resulting nuclei from nuclear fission (like in a nuclear power plant) weigh less together than the original nucleus did. Because that energy is still there when the nuclei are brought to rest, however, it looks exactly like a rest mass.

BlackGriffen
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Dakar
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Nov 11, 2004, 02:53 PM
 
Originally posted by BlackGriffen:
No, light has zero rest mass. The thing is that gravity doesn't couple to mass, it couples to energy. Photons definitely have energy, and thus are affected by gravity.

That is the most commonly used definition of matter, I think: anything that has a rest mass.

Here is the equation for the energy of any particle (like an electron or photon) in relativity:

E = sqrt((m*c^2)^2 + (p*c)^2)

where: m = rest mass, c = speed of light, p = momentum, E = energy

So, to find out if something is matter, you use a lower and lower momentum example of it and find out how much energy is left over. Thing is, photons disappear entirely as their momentum goes to zero.

Much of the rest mass of a proton or nucleus, for instance, actually comes from the potential energy of the quarks bound up in them and not from the constituent quarks themselves. This is why the resulting nuclei from nuclear fission (like in a nuclear power plant) weigh less together than the original nucleus did. Because that energy is still there when the nuclei are brought to rest, however, it looks exactly like a rest mass.

BlackGriffen
That's interesting. Is light capable of coming to rest however?

As for the nuclei in fission weighing less than the original nucleus, I though that was ecause some of te mass was converted to the energy and therefore lost in that fashion.

Edit: Terminology.
( Last edited by Dakar; Nov 11, 2004 at 03:03 PM. )
     
Shaddim
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Nov 11, 2004, 02:57 PM
 
Originally posted by Dakar:
That's interesting. Is light capable of coming to rest however?

As for the nuclei in fission weighing less than the original nuclei, I though that was ecause some of te mass was converted to the energy and therefore lost in that fashion.
Have they been able to find any "decaying" photons yet? Just wondering.
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Nov 11, 2004, 05:43 PM
 
Originally posted by Dakar:
That's interesting. Is light capable of coming to rest however?

As for the nuclei in fission weighing less than the original nucleus, I though that was ecause some of te mass was converted to the energy and therefore lost in that fashion.

Edit: Terminology.
That's the point. One way of bringing a particle to rest is by "running" to catch up with it. As you go faster, however, the wavelength of the light gets changed by a combination of doppler and relativistic effects. Essentially, the wavelengths gets longer the faster you go in the same direction as the photon (and the frequency goes down). This process doesn't have an end to it, however, because as you get arbitrarily close to the speed of light, the wavelength becomes arbitrarily large (=> the frequencey become arbitrarily small). So, as you drop the momentum (h/wavelength) to zero, the energy (h * frequency) goes to zero as well. Thus, there is no rest mass.

I probably shouldn't have included that bit about fission - it's not technically more than tangential. Yes, if you take the products of fission and weigh them against the ingredients - by any means you should choose (gravity, collisions, etc) - the ingredients have more mass. The point I'm trying to get across here is that rest mass is literally the measured energy of a thing divided by c^2 when it's momentum is zero. So, for instance, say we weighed you. Then we took you apart, atom by atom, and weighed them all one by one (all 2.6e30 of them). The net mass of the molecules should be about 0.1 mg less than yours because the thermal energy that was inside of you would be calculated out as the kinetic energy of the molecules. Why? Because when we brought you to rest to measure your mass, we did not stop all of the molecules inside of you. When we measure all of the molecules separately, however, we do. That should give you some idea of how much energy is tied up just in keeping you, and everything around you, warm.

The point? Mass is just a form of energy that can be "brought to rest." When you measure mass you're actually measuring how much energy a thing contains when its overall kinetic energy is removed (in other words, when it is brought to rest). The constituent parts can still have kinetic energy, which is included in the mass of the object, and potential energies (positive and negative).

BlackGriffen
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Nov 11, 2004, 06:00 PM
 
Originally posted by BlackGriffen:
That's the point. One way of bringing a particle to rest is by "running" to catch up with it. As you go faster, however, the wavelength of the light gets changed by a combination of doppler and relativistic effects. Essentially, the wavelengths gets longer the faster you go in the same direction as the photon (and the frequency goes down). This process doesn't have an end to it, however, because as you get arbitrarily close to the speed of light, the wavelength becomes arbitrarily large (=> the frequencey become arbitrarily small). So, as you drop the momentum (h/wavelength) to zero, the energy (h * frequency) goes to zero as well. Thus, there is no rest mass.
Ah, that put things into perspective for me, though it does bring up some imaginative questions as to what is gravity if it is able to interect with light in such a manner as to restrict it.

Originally posted by BlackGriffen:
I probably shouldn't have included that bit about fission - it's not technically more than tangential. Yes, if you take the products of fission and weigh them against the ingredients - by any means you should choose (gravity, collisions, etc) - the ingredients have more mass. The point I'm trying to get across here is that rest mass is literally the measured energy of a thing divided by c^2 when it's momentum is zero. So, for instance, say we weighed you. Then we took you apart, atom by atom, and weighed them all one by one (all 2.6e30 of them). The net mass of the molecules should be about 0.1 mg less than yours because the thermal energy that was inside of you would be calculated out as the kinetic energy of the molecules. Why? Because when we brought you to rest to measure your mass, we did not stop all of the molecules inside of you. When we measure all of the molecules separately, however, we do. That should give you some idea of how much energy is tied up just in keeping you, and everything around you, warm.
Yeah, that makes sense too. Correct me if my correlation is incorrect, but the energy loss could be blamed on whatever ws holding the atoms together was released when they were taken apart?

Originally posted by BlackGriffen:
The point? Mass is just a form of energy that can be "brought to rest."

BlackGriffen
That's a pretty basic tenet of physics as far as I remember, but thanks for the extra info.
     
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Nov 12, 2004, 01:51 AM
 
Originally posted by Dakar:
Ah, that put things into perspective for me, though it does bring up some imaginative questions as to what is gravity if it is able to interect with light in such a manner as to restrict it.
Don't quote me on this, because I haven't studied general relativity yet, but this is what I understand. In general relativity one of the effects of gravity is to slow down time. The event horizon of a black hole is where gravity becomes so powerful that time stops.

Yeah, that makes sense too. Correct me if my correlation is incorrect, but the energy loss could be blamed on whatever ws holding the atoms together was released when they were taken apart?
No, not really. It's actually just the opposite: the composite nucleus doesn't have as much binding energy per proton/neutron as the separate nuclei. I'm beginning to regret my description of it earlier. The negative potential energy (strong force) holding nuclei together actually reduces the mass of the composite compared to it's constituents. It's a fine distinction, I guess, that the mass of a uranium nucleus is reduced less by the strong force than the mass of what it breaks up into, but an important one.

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mikellanes
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Nov 12, 2004, 01:17 PM
 
Originally posted by BlackGriffen:
In general relativity one of the effects of gravity is to slow down time. The event horizon of a black hole is where gravity becomes so powerful that time stops.
That is how it is understood.

http://www.weburbia.demon.co.uk/physics/relativity.html
http://www.physics.adelaide.edu.au/~dkoks/Faq/

Does Gravity Travel at the Speed of Light?
http://math.ucr.edu/home/baez/physic...rav_speed.html
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Nov 12, 2004, 01:44 PM
 
I Think I heard the recent measurements of the so-called dark matter seemed to indicate that the universe is gonna in perpetual expansion. Can somebody in the know enlighten me?
     
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Nov 12, 2004, 03:27 PM
 
We all know the earth was created on Oct. 11, 1750 AD at 3:15am.

God created it... and created the earth with everything on it... THINKING that it was much older. There are no stars... they are just pin holes in the tarp around our universe...

OK, prove me wrong...
     
PB2K
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Nov 14, 2004, 10:28 PM
 
oh topicstarter :

YOU WONT MINDBOGGLE US WITH YOUR PUNY QUESTIONS ABOUT EVOLUTION.
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SimpleLife
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Nov 14, 2004, 11:19 PM
 
Originally posted by Mithras:

As for the allegation that perhaps the Universe itself is infinite, perfect, and its own uncaused cause: no. The Universe is merely physical, which is not sufficient for those attributes.
I disagree.

The Universe is also imaginary. The Human brain, as a by product of the Creation has extended Reality beyond the realm of the physical; it is part, or a subset of the Universe. The problem lies in the belief that imagination is enough to explain the existence of the universe, or in imagining that you require a being of some sort to create such Universe.
     
SimpleLife
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Nov 14, 2004, 11:24 PM
 
Originally posted by mikellanes:
Since you wanted to get philosophical, how about this... Because this is what boggles my mind. If there was no "place" north of the north pole, then how could you ever go south to get to the north pole

Now relate that to what we are discussing (or what I am discussing with myself as the case is) and some things fall in to place, no?

Here are some current theories on the universe creation.

1) A cyclic universe theory-There is another universe just like ours before the Big Bang, it met its end and our current universe exists as a result.

2) Multiverse theory- Our universe might just be one of the many universes "born" in an infinite cosmic ocean due to quantum fluctation

3) Baby universe theory- Our universe was originated from an evaporated black hole found in another universe (note that the physics in the "parent" universe might not be the same as ours)

[This one's particularly interesting. If the physics in the parent universe affected the child universe to some degree, something a lot like evolution would take place. Universes that were good at making black holes would come to predominate. It wouldn't exactly be the same as biological evolution, because there would be no competition amongst universes for resources, but there would be some kind of natural selection. Universes that destroyed themselves too early to form black holes would not reproduce.]

4) Parallel universe theory- Our universe was one of the various existing unverses found across the multiverse and each universe's natural laws was almost similar to each other and they existed because of multiples probablity results of the wave function.

5) Creationist theory- Well, you know the myth.
6) Timeless Universe: a series of "nows" are coexisting in sequence or multiple copies of "nows" are neibourhing one another and our consciousness makes some sense of it. Let's not forget the subjectivity of our main tool of investigation: the brain, which is made of the same substance of that it is measuring.
     
SimpleLife
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Nov 14, 2004, 11:25 PM
 
Originally posted by BlackGriffen:
Where the first atoms came from is easy: they formed when the universe cooled sufficiently for the photons to decouple from electrons, protons, et al. The short answer: when the universe cooled to about 150,000 K (about 150,000 C, or 280,000 F). Background radiation is the light left over from that moment - extremely red shifted.

But then you'd know that if you'd bothered to read about big bang theory instead of just saying, "God did it," all of the time.

The next question always asked is, "What caused the big bang?" or, a necessary condition for knowing a cause, "What was before the big bang?" Guess what? The big bang is supposed to be when space came into existence. time is included in that picture. Because "before" and "cause" are necessarily temporal concepts, the current theories would have to be wrong for either to make sense. What would make more sense to ask, and be consistent with current well tested theories, would be, "What exists outside of time and space?" The answer to that is, simply, we don't know. Without some evidence that something exists beyond the dimensions that came into existence with the big bang, it isn't profitable to speculate on what may be beyond the universe.

BlackGriffen
That makes sense to me.
     
SimpleLife
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Nov 14, 2004, 11:30 PM
 
Originally posted by CreepingDeth:
You may be right. But if two universes are supposed to be coexistent, then there would have to be something that links them together like a bridge. Since travel through black holes is out of the question, and wormholes are most likely science fiction, it leads me to believe given our current knowledge, there would have to be some sort of phenomena like a wormhole or something that defies reality that somehow gives the universes a relation, if we assume that your theory is true. Then what do you believe is the answer to that?
Wormholes, as well as Black Holes are still theoritical objects.

But if you were to travel near the speed of light, the universe around you would be shaped like a Black Hole horizon. Travelling through a Black Hole may be travelling at the speed of light.

Wormholes do not defy reality if they exist.
     
SimpleLife
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Nov 14, 2004, 11:33 PM
 
Originally posted by mikellanes:
Very interesting post, what is your background if you don't mind me asking.



From what I have studied recently, time is always around, whether we observe it or not.
To think that the universe just came out of nothing like that would require something like the external impulse of God.

I think the older BB theory is nothing more than a secular creation myth.
Let me know what you think about: http://www.marxist.com/science/bigbang.html

I am interested in your opinion.
It all goes down to "what is".

If time is a dimension, and space is a dimension, and that both are tied to the universe, then, both time and space were created with the universe. These aspects are bound to reality.
     
SimpleLife
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Nov 14, 2004, 11:39 PM
 
Originally posted by AKcrab:
I think we need to forget time.
We created time, based on our revolutions around the sun. Is it really universal? The universe doesn't care about our revolutions around the sun, we're just one of eleventy-billion planets orbiting a star at some random interval.

What happens when we take time out of our equations?
Actually, we can reframe the whole debate around causality. If there is no causality, there is no time.

"The cat that jumps in the air and the cat that lands are 2 different beings." (Julian Barbour, The End Of Time").

This resolves the debate and plugs time as a cognitive process.
     
SimpleLife
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Nov 14, 2004, 11:45 PM
 
Originally posted by mikellanes:
Good Morning!!

Hmm interesting, what does happen when we take time out of the equation? Not much Id say, it is relative, which is why we measure it in a relative way.

I do think time is universal, at least in our universe, everything that happens takes time, you can define time in many different ways but the fact that getting up and walking to the shower (that is what I am about to do) can not be instantaneous is in itself the reality of time. IMO.
Not if you take humans out of the equation. If time dilates with the speed of light, and observers disagree on what appeared to be similar events, time, or rather, causality is not as we comprehend.

The same goes with the rules leading quantum mechanics; identities are impossible, desintegration of particles lead to the same particles, entanglement of photons create paradoxes that seem to go againts the rules guiding our understanding of the universe...

This world has nothing to do with the apple morsel you chew by its tree, as tasteful it may be, senses are just sets of molecules interacting in ways we still do not comprehend.

We are like the blindfolded boxer trying to repair a watch with his gloves on...
     
SimpleLife
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Nov 14, 2004, 11:51 PM
 
Originally posted by BlackGriffen:
...

"POSTREMO NEMO AEGROTUS QUIDQUAM SOMNIAT TAM INFANDUM, QUOD NON ALIQUIS DICAT PHILOSOPHUS." --Varro, Fragmenta ("No madman has ever dreamed up anything so weird that some philosopher will not say it.")

BlackGriffen
     
SimpleLife
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Nov 14, 2004, 11:57 PM
 
Originally posted by BlackGriffen:
That's the point. One way of bringing a particle to rest is by "running" to catch up with it. As you go faster, however, the wavelength of the light gets changed by a combination of doppler and relativistic effects. Essentially, the wavelengths gets longer the faster you go in the same direction as the photon (and the frequency goes down). This process doesn't have an end to it, however, because as you get arbitrarily close to the speed of light, the wavelength becomes arbitrarily large (=> the frequencey become arbitrarily small). So, as you drop the momentum (h/wavelength) to zero, the energy (h * frequency) goes to zero as well. Thus, there is no rest mass.

I probably shouldn't have included that bit about fission - it's not technically more than tangential. Yes, if you take the products of fission and weigh them against the ingredients - by any means you should choose (gravity, collisions, etc) - the ingredients have more mass. The point I'm trying to get across here is that rest mass is literally the measured energy of a thing divided by c^2 when it's momentum is zero. So, for instance, say we weighed you. Then we took you apart, atom by atom, and weighed them all one by one (all 2.6e30 of them). The net mass of the molecules should be about 0.1 mg less than yours because the thermal energy that was inside of you would be calculated out as the kinetic energy of the molecules. Why? Because when we brought you to rest to measure your mass, we did not stop all of the molecules inside of you. When we measure all of the molecules separately, however, we do. That should give you some idea of how much energy is tied up just in keeping you, and everything around you, warm.

The point? Mass is just a form of energy that can be "brought to rest." When you measure mass you're actually measuring how much energy a thing contains when its overall kinetic energy is removed (in other words, when it is brought to rest). The constituent parts can still have kinetic energy, which is included in the mass of the object, and potential energies (positive and negative).

BlackGriffen
It is really something to witness such skills in explaining this so well.

Thank you BlackGriffen!
     
BlackGriffen
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Nov 15, 2004, 12:10 AM
 
Originally posted by SimpleLife:
It is really something to witness such skills in explaining this so well.

Thank you BlackGriffen!
Why, you're welcome. I do try, and I'm glad you enjoyed my posts.

BG
I do not feel obliged to believe that the same God who has endowed us with sense, reason, and intellect has intended us to forgo their use. -Galileo Galilei, physicist and astronomer (1564-1642)
     
SimpleLife
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Nov 15, 2004, 12:12 AM
 
Originally posted by villalobos:
I Think I heard the recent measurements of the so-called dark matter seemed to indicate that the universe is gonna in perpetual expansion. Can somebody in the know enlighten me?
I do not know much but my understanding is that from the (hypothesized) Big Bang, a certain momentum was provided as energy got converted into mass.

But there is something else: the fact that the universe is expanding, meaning that space is extending with time. Think of it as a stretching; not only is matter filling up the void, but so is space. A bit like filling up a void. In doing so, the total amount of energy is going down as the binding forces lose their grip.

The more there is space, the less there is entropy, or, if you prefer, the lower the probabilities of particles to hit one another and provide energy.

Here is something to chew on the "Big Chill". That is way better than I could explain.

     
BlackGriffen
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Nov 15, 2004, 02:02 AM
 
Originally posted by SimpleLife:
I do not know much but my understanding is that from the (hypothesized) Big Bang, a certain momentum was provided as energy got converted into mass.

But there is something else: the fact that the universe is expanding, meaning that space is extending with time. Think of it as a stretching; not only is matter filling up the void, but so is space. A bit like filling up a void. In doing so, the total amount of energy is going down as the binding forces lose their grip.

The more there is space, the less there is entropy, or, if you prefer, the lower the probabilities of particles to hit one another and provide energy.

Here is something to chew on the "Big Chill". That is way better than I could explain.

How can entropy go down as volume goes up and number of particles remains constant? It's my understanding that entropy goes up as the logarithm of the volume. After all, if there's more volume available, there are more states the system can take. The short and simple definition of entropy is:

S = k ln(W)

k is Boltzmann's constant, S is entropy, and W is the number of states that are consistent with the constraints placed on the system (eg known total energy, number of particles, volumes, etc). You might think of entropy as a measure of how many ambiguities there are in what you know about the system. For instance, when I flip a coin and hide the result form you, you don't know if the the coin is heads or tails. Thus, the entropy is k*ln(2) because there are two states consistent with what we know about the coin. Now, I'm leaving off the vast majority of the actual entropy from what we don't know about what's going on at the microscopic level, but for a thought experiment like this it's safe to pretend otherwise.

What else. Binding forces are a negative energy. Literally, the binding energy is how how much lower the energy is than the obstacle. You reduce binding energy, and you increase the overall energy of the system. Another way to think of it is that in order to break apart a system that is bound together you have to add energy (put work into) the system. This could be part of why physicists postulate that a dark energy of some kind must exist in order to spread out the gravitationally bound matter.

BlackGriffen
I do not feel obliged to believe that the same God who has endowed us with sense, reason, and intellect has intended us to forgo their use. -Galileo Galilei, physicist and astronomer (1564-1642)
     
SimpleLife
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Nov 15, 2004, 07:28 PM
 
Originally posted by BlackGriffen:
How can entropy go down as volume goes up and number of particles remains constant? It's my understanding that entropy goes up as the logarithm of the volume. After all, if there's more volume available, there are more states the system can take. The short and simple definition of entropy is:

S = k ln(W)

k is Boltzmann's constant, S is entropy, and W is the number of states that are consistent with the constraints placed on the system (eg known total energy, number of particles, volumes, etc). You might think of entropy as a measure of how many ambiguities there are in what you know about the system. For instance, when I flip a coin and hide the result form you, you don't know if the the coin is heads or tails. Thus, the entropy is k*ln(2) because there are two states consistent with what we know about the coin. Now, I'm leaving off the vast majority of the actual entropy from what we don't know about what's going on at the microscopic level, but for a thought experiment like this it's safe to pretend otherwise.

What else. Binding forces are a negative energy. Literally, the binding energy is how how much lower the energy is than the obstacle. You reduce binding energy, and you increase the overall energy of the system. Another way to think of it is that in order to break apart a system that is bound together you have to add energy (put work into) the system. This could be part of why physicists postulate that a dark energy of some kind must exist in order to spread out the gravitationally bound matter.

BlackGriffen
I had to get some reading to make sure I understand that post of yours...

http://www.chiark.greenend.org.uk/~s...d the Universe
Entropy is a measure of the lack of order in the energy. There is no definite value of entropy for a given system (as there is for, say, mass), as entropy is a purely statistical measure. When there is zero entropy, all the energy can be used. As the entropy increases, available energy decreases until, with maximum entropy, no useful energy is available
Indeed you are right.

Thank you for the little expose and forcing me to work a bit here!
     
 
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