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Massless things


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#21 Strange

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Posted 19 January 2017 - 09:19 AM

The 100% conversion of mass to energy or energy to mass. 

 

 

That doesn't seem right: nuclear fission (or fusion) converts a fraction of the mass to energy. 


Isn't Einstein's Mass-Energy equivalence purely theoretical until certain conditions such as object traveling at least 10% of c? 

 

 

No. 


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#22 Bender

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Posted 19 January 2017 - 11:46 AM

Isn't Einstein's Mass-Energy equivalence purely theoretical until certain conditions such as object traveling at least 10% of c? Gravity waves meet that condition. 

 

The 100% conversion of mass to energy or energy to mass. 

Some examples:

- the nucleus of an atom has less mass than the protons and neutrons separately

- a molecule has less mass than the atoms it consists of separately (at least for stable molecules)

- a charged battery has more mass than a depleted one

 

The last two differences are, as far as I know, not measurable, which makes it easy to forget it is there. That is also the reason that a nuclear reaction is so much more powerful than chemical reactions, because there the difference is measurable.


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#23 Nedcim

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Posted 19 January 2017 - 11:38 PM

 

 

That doesn't seem right: nuclear fission (or fusion) converts a fraction of the mass to energy. 

 

 

Ok, so It's only the mass change that is involved. Nevertheless, there are only certain conditions where any measurable conversion is going to take place  Nuclear fission requires high speed neutrons. Nuclear fusion requires extremely high temperature environment.The mass change involved in energy flowing through medium would undetectable.     

Some examples:

- the nucleus of an atom has less mass than the protons and neutrons separately

- a molecule has less mass than the atoms it consists of separately (at least for stable molecules)

- a charged battery has more mass than a depleted one

 

The last two differences are, as far as I know, not measurable, which makes it easy to forget it is there. That is also the reason that a nuclear reaction is so much more powerful than chemical reactions, because there the difference is measurable.

Since the first one is measurable it is particularly interesting, but strange things happen at the atomic scale.  


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#24 Strange

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Posted 19 January 2017 - 11:39 PM

 

Ok, so It's only the mass change that is involved. Nevertheless, there are only certain conditions where any measurable conversion is going to take place  Nuclear fission requires high speed neutrons. Nuclear fusion requires extremely high temperature environment.The mass change involved in energy flowing through medium would undetectable.     

 

 

What?


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#25 Nedcim

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Posted 20 January 2017 - 03:19 AM

 

 

What?     

If you disagree then explicitly state why but don't ask vague questions.  


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#26 Strange

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Posted 20 January 2017 - 08:22 AM

Ok, so It's only the mass change that is involved.

 
 
Only what mass changed that is involved in what?
 

Nevertheless, there are only certain conditions where any measurable conversion is going to take place

 
True. As already noted, the mass change in chemical reactions is (as far as I know) too small to measure. That doesn't mean it doesn't happen. So how is it relevant?
 

Nuclear fission requires high speed neutrons

 
So what?
 

. Nuclear fusion requires extremely high temperature environment.

 
So what?
 

The mass change involved in energy flowing through medium would undetectable.


What does "energy flowing through medium" mean?

The mass change would be measurable if the energy change were large enough so, again, so waht?
 

Since the first one is measurable it is particularly interesting, but strange things happen at the atomic scale.


What strange things?

And how is it relevant?

In summary, you have said nothing relevant to mass-energy equivalence, so what is your point?


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#27 Nedcim

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Posted Yesterday, 05:17 AM

 
 
Only what mass changed that is involved in what?
 

 

Obviously, in mass energy equivalence. 

 

True. As already noted, the mass change in chemical reactions is (as far as I know) too small to measure. That doesn't mean it doesn't happen. So how is it relevant?

 

 A mass change  is expected to occur in chemical reactions, but until it is proven with measured quantities, it's just theoretical principle . Do you really need to ask the relevancy for something that may or may not happen? 

So what?
 

So what?

 


Strict conditions

 


The mass change would be measurable if the energy change were large enough so, again, so waht?

 

How large of an energy change? Until direct measured quantities of mass change are recorded from mechanical waves, it is only a theoretical principle so why make that assumption?  Maybe mass energy equivalence occurs only during strict conditions. 
 


What strange things?

 


An earlier post just gave two examples. 


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#28 Mordred

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Posted Yesterday, 06:02 AM

Lets take an everyday tested example. The LHC, in order to increase a proton to the speeds it reaches the energy requirements to accelerate the proton matches those predicted by relativity due to inertial mass increase. Or top quarks at the LHC

In fact relativity is tested daily with the LHC, CERN etc. That is precisely how CERN created the Higgs boson whose rest mass exceeds the combined mass of both protons. Or top quarks at the LHC.

Edited by Mordred, Yesterday, 06:08 AM.

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http://www.einsteins.../LightCone.html
http://cosmology101.wikidot.com/main
http://cosmocalc.wikidot.com/start
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#29 Strange

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Posted Yesterday, 10:23 AM

Obviously, in mass energy equivalence. 

 

 A mass change  is expected to occur in chemical reactions, but until it is proven with measured quantities, it's just theoretical principle . Do you really need to ask the relevancy for something that may or may not happen? 

Strict conditions

 

How large of an energy change? Until direct measured quantities of mass change are recorded from mechanical waves, it is only a theoretical principle so why make that assumption?  Maybe mass energy equivalence occurs only during strict conditions. 
 

An earlier post just gave two examples. 

 

 

So you think the theory is only valid for specific values where it is measured? 

 

Do you apply this to all theories? For example, we have Newton's F=ma. Do you think that is only proven correct for the specific values of F, m and a that have been tested? And for other values it might not work?


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#30 J.C.MacSwell

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Posted Yesterday, 02:10 PM

Obviously, in mass energy equivalence. 

 

 A mass change  is expected to occur in chemical reactions, but until it is proven with measured quantities, it's just theoretical principle . Do you really need to ask the relevancy for something that may or may not happen? 

Strict conditions

 

How large of an energy change? Until direct measured quantities of mass change are recorded from mechanical waves, it is only a theoretical principle so why make that assumption?  Maybe mass energy equivalence occurs only during strict conditions. 
 

An earlier post just gave two examples. 

Occam's razor. Until we have an example where mass energy equivalence does not occur, or it would explain something that is otherwise unexplainable. it is the simplest assumption based on current physics...similar to assuming undetectable pink unicorns do not exist when no one is looking, even though no one has proven they don't exist.


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