Matter <--> Energy Conversions: A Phase Transition?

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Glenn
Matter <--> Energy converions

Is it accurate or inaccurate to think of matter <-->energy conversions to be a "Phase Transition" in the same way that ice to water to steam conversions are examples of phase transitions? And Why?

Thanks,
Glenn
 
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it is accurate. Matter is energy and energy is mass. E = mc^2
 
Nenad said:
it is accurate. Matter is energy and energy is mass. E = mc^2
You missed a coefficient.
E = \gamma mc^{2}
 
Glenn said:
Is it accurate or inaccurate to think of matter <-->energy conversions to be a "Phase Transition" in the same way that ice to water to steam conversions are examples of phase transitions? And Why?

Thanks,
Glenn

First off it is mass-energy conversion and not matter-energy convertsion. The former has a precise meaning while the later is foggy since "matter" has never been something that one can reasonably quantity unless you replace it with the term "mass".

Second off - It is inaccurate to think of matter-energy conversion as a phase transition. You're talking about two separate things in mass-energy conversion wherein phase transitions you're talking about the same thing in different states. Mass should never be thought of as frozen energy.

Why? The very meaning of E = mc2 is that an increase in energy can result in an increase in mass and vice versa. There is no reason to think of that as a phase transition. For example: Suppose you blew air into a rubber balloon. Then the balloon would blow up and the surface area o the balloon would increase. Therefore, increase air - increase surface area. Or you can simply say, increase volume - increase surface area. But what you can't say is that the surface is a phase of volume or that volume and surface are two aspects of the same thing.

Pete
 
Last edited:
pmb_phy said:
The very meaning of E = mc2 is that an increase in energy can result in an increase in mass and vice versa.
No, it is missing the zero subscript on the energy, but means that mass is rest energy.
 
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