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Author
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Topic: Big Bang Critics
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ringo
Member (Idle past 730 days) Posts: 20940 From: frozen wasteland Joined: 03-23-2005
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Message 91 of 130 (335067)
07-25-2006 12:56 AM
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Reply to: Message 89 by cavediver
07-24-2006 6:18 PM
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Re: Confusing Matter with Mass {as in E=MC^2}
cavediver writes: Mass is a property of matter AND energy. Yes, that was implied. I was trying to simplify for poor Philip.  You have succeeded in busting my point. Apparently, the rest of us are all confused. Some of us just don't know it. 
Help scientific research in your spare time. No cost. No obligation.Join the World Community Grid with Team EvC
| This message is a reply to: | | | Message 89 by cavediver, posted 07-24-2006 6:18 PM | | cavediver has replied |
| Replies to this message: | | | Message 93 by cavediver, posted 07-25-2006 7:06 AM | | ringo has not replied |
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cavediver
Member (Idle past 3962 days) Posts: 4129 From: UK Joined: 06-16-2005
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Message 92 of 130 (335098)
07-25-2006 6:31 AM
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Reply to: Message 90 by NosyNed
07-24-2006 7:54 PM
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Re: Confusing Matter with Mass {as in E=MC^2}
This is given me knew insights into this stuff that I've never stumbled across before. Cool  I couldn't ask for anything better than that...
| This message is a reply to: | | | Message 90 by NosyNed, posted 07-24-2006 7:54 PM | | NosyNed has not replied |
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cavediver
Member (Idle past 3962 days) Posts: 4129 From: UK Joined: 06-16-2005
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Message 93 of 130 (335103)
07-25-2006 7:06 AM
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Reply to: Message 91 by ringo
07-25-2006 12:56 AM
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Re: Confusing Matter with Mass {as in E=MC^2}
Apparently, the rest of us are all confused Given the amount of disinformation out there, that is not at all surprising. But it is also a minefield of definitions which can change meaning depending on context. Words like matter, mass and energy are not really part of the terminology this deep into the maths/physics world, and some translation is needed.
| This message is a reply to: | | | Message 91 by ringo, posted 07-25-2006 12:56 AM | | ringo has not replied |
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sidelined
Member (Idle past 6226 days) Posts: 3435 From: Edmonton Alberta Canada Joined: 08-30-2003
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Message 94 of 130 (335129)
07-25-2006 9:59 AM
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Reply to: Message 89 by cavediver
07-24-2006 6:18 PM
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Re: Confusing Matter with Mass {as in E=MC^2}
cavediver
Mass is a property of matter AND energy. So if mass is a property of energy how is it that mass and energy are equivalent in E=MC^2?
| This message is a reply to: | | | Message 89 by cavediver, posted 07-24-2006 6:18 PM | | cavediver has replied |
| Replies to this message: | | | Message 97 by cavediver, posted 07-25-2006 1:27 PM | | sidelined has replied |
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2ice_baked_taters
Member (Idle past 6169 days) Posts: 566 From: Boulder Junction WI. Joined: 02-16-2006
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Message 95 of 130 (335152)
07-25-2006 12:04 PM
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In the first seconds after the Big Bang, there was no matter, scientists suspect. Just energy. As the universe expanded and cooled, particles of regular matter and antimatter were formed in almost equal amounts Not a chance Mass is a property of matter AND energy. Mass is what gravity couples to, it is what curves space. In Relativity we call it stress-energy just to be obtuse. Matter is the name we give to the excitations of a specific type of quantum energy field: fermionic fields give rise to fermions. They tend to have mass, but not very much. Examples are quarks, electrons, neutrinos, etc. Solid stuff (technical term) is made up of both matter fermions and "force" bosons. The mass of solid stuff consists of the mass of the actual matter fermions (tiny) and the effective mass of all of the binding energy holding the solid stuff together (huge). About 0.1% of the mass of a proton comes from the mass of the three matter fermions (quarks) making up the proton. To say you can convert matter to energy is a little misleading. You can convert a pair of fermions into a pair of photons. Fermions have mass, photons do not. So in a sense you have convereted matter to energy, but what you have really done is exchange a pair of particles called matter for a different pair of particles which aren't called matter!! After this I see no reason to call a photon a particle. It doesn't fit in the box. If something has no mass it should not physically exist. Therefore it either has mass in such a small quantity that it has not been detected or it is something other than physical. In this latter it is more likely that our understanding of physical is incorrect.
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cavediver
Member (Idle past 3962 days) Posts: 4129 From: UK Joined: 06-16-2005
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Apology and clarification
If something has no mass it should not physically exist. Ok, I made a bit of a screw-up in what I said. Specifically:
quote:
Fermions have mass, photons do not
What I should have said is that photons do not have a rest-mass, which is a different concept. They still have an energy, given by their frequency times Planck's Constant, and that energy will couple to gravity, so photons do have an associated energy-mass.
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cavediver
Member (Idle past 3962 days) Posts: 4129 From: UK Joined: 06-16-2005
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Message 97 of 130 (335172)
07-25-2006 1:27 PM
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Reply to: Message 94 by sidelined
07-25-2006 9:59 AM
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Re: Confusing Matter with Mass {as in E=MC^2}
So if mass is a property of energy how is it that mass and energy are equivalent in E=MC^2? This is back to this confusion of terms I was talking about. I think "property" is the wrong word. Mass is a measure of the energy content of a volume of space in the context of gravitation.
| This message is a reply to: | | | Message 94 by sidelined, posted 07-25-2006 9:59 AM | | sidelined has replied |
| Replies to this message: | | | Message 99 by sidelined, posted 07-31-2006 2:28 AM | | cavediver has not replied |
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1.61803
Member (Idle past 1822 days) Posts: 2928 From: Lone Star State USA Joined: 02-19-2004
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Message 98 of 130 (335229)
07-25-2006 4:20 PM
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Energy. No one knows from whence it came. Not physicist, not theologist. Anything prior to the very limits of what physics can describe; is speculative on all counts. How can someone see they're own eye? You can see a reflection of it in a mirror. Like we can see manifestations of energy and matter and the interactions of these states. But to pluck out the eye and look at it with the other is still relying on one thing trying to percieve another. Definitions, descriptions, equations are all inadequate when it comes down to the nittygritty. Whats that phylosophers linguists' name Lechetenstien? or something...What good is language if we are all paralized to mute mootness. My dos centavos. Edited by 1.61803, : correct the spelling of ligist to linguist.
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sidelined
Member (Idle past 6226 days) Posts: 3435 From: Edmonton Alberta Canada Joined: 08-30-2003
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Message 99 of 130 (336809)
07-31-2006 2:28 AM
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Reply to: Message 97 by cavediver
07-25-2006 1:27 PM
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Re: Confusing Matter with Mass {as in E=MC^2}
cavediver
Mass is a measure of the energy content of a volume of space in the context of gravitation. How does mass relate to inertia in the context of this definition?
| This message is a reply to: | | | Message 97 by cavediver, posted 07-25-2006 1:27 PM | | cavediver has not replied |
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happy_atheist
Member (Idle past 5232 days) Posts: 326 Joined: 08-21-2004
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2ice_baked_taters writes: After this I see no reason to call a photon a particle. It doesn't fit in the box. If something has no mass it should not physically exist. Therefore it either has mass in such a small quantity that it has not been detected or it is something other than physical. In this latter it is more likely that our understanding of physical is incorrect. I think this comes back to cavedivers distinction between fermionic mass and bosonic mass. Photons have no rest mass (which I assume means fermionic mass). They do however have momentum, which is related to mass, so I don't think it's true to say that they have no mass whatsoever.
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2ice_baked_taters
Member (Idle past 6169 days) Posts: 566 From: Boulder Junction WI. Joined: 02-16-2006
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I think this comes back to cavedivers distinction between fermionic mass and bosonic mass. Photons have no rest mass (which I assume means fermionic mass). They do however have momentum, which is related to mass, so I don't think it's true to say that they have no mass whatsoever. After doing a bit of reading I have come to understand that there is no evidence indicating that what we call photons have no rest mass. There is also no clear definiton of photon.
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happy_atheist
Member (Idle past 5232 days) Posts: 326 Joined: 08-21-2004
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2ice_baked_taters writes: After doing a bit of reading I have come to understand that there is no evidence indicating that what we call photons have no rest mass. There is also no clear definiton of photon. What is it that you've read? Off the top of my head, photons travel at c. This demands that they have zero rest mass as long as the relativistic equations are correct (and I've not heard of any evidence that contradicts them, but if there is I'll stand corrected). It's not possible for anything to travel at c if it doesn't have zero rest mass, from a relativistic point of view. I think I'll have to leave it to cavediver for a more in depth response though.
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2ice_baked_taters
Member (Idle past 6169 days) Posts: 566 From: Boulder Junction WI. Joined: 02-16-2006
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Off the top of my head, photons travel at c. This demands that they have zero rest mass as long as the relativistic equations are correct (and I've not heard of any evidence that contradicts them, but if there is I'll stand corrected). It's not possible for anything to travel at c if it doesn't have zero rest mass, from a relativistic point of view. Everything physical has mass or it does not exist physically. If something truely has no mass then it cannot be physical in nature. Relativity simply is not describing the picture correctly.
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cavediver
Member (Idle past 3962 days) Posts: 4129 From: UK Joined: 06-16-2005
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Everything physical has mass or it does not exist physically How do you know this? And more importantly, to what kind of mass are you preferring? Rest mass? Effective mass (via E=mc^2)?
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Percy
Member Posts: 23144 From: New Hampshire Joined: 12-23-2000 Member Rating: 5.8
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2ice_baked_taters writes: Everything physical has mass or it does not exist physically. If something truely has no mass then it cannot be physical in nature. You have to be careful while maneuvering around the terminology. If you read cavediver's Message 96 and Message 97 you'll see photons do have a "mass", but it's in the form of energy which follows the E=mc 2 relationship. The mass of a photon is, I believe, what cavediver is calling the "energy mass". The photon does not have a rest mass in the way that particles like electrons and protons do. The reason I mentioned terminology is that your statement, "Everything physical has mass or it does not exist physically," is impossibly vague. By physical do you mean anything that exists, or only anything physical like an anvil? By mass do you mean rest mass or energy mass? If I were to seek correct interpretations of your statement, one would be, "Everything physical (i.e., made up of particles) has a rest mass," and the other would be, "Everything that exists has an energy mass." --Percy
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