"Paul.B.Andersen" <relativity@paulba.no> wrote or quoted:--- Synchronet 3.21a-Linux NewsLink 1.2
:that mass could be converted to energy as
:predicted by Einstein's E = mc?.
I can spot three mistakes here right off the bat.
"Paul.B.Andersen" <relativity@paulba.no> wrote or quoted:
:that mass could be converted to energy as
:predicted by Einstein's E = mc-#.
I can spot three mistakes here right off the bat.
First, the phrase "mass could be converted to energy" is based on
a misconception, since mass already /is/ a form of energy - there's no
"conversion" happening. It's like saying, "water can be turned into a
liquid" - no, water /is/ a liquid.
...
"Paul.B.Andersen" <relativity@paulba.no> wrote or quoted:
:that mass could be converted to energy as
:predicted by Einstein's E = mc-#.
I can spot three mistakes here right off the bat.
First, the phrase "mass could be converted to energy" is based on
a misconception, since mass already /is/ a form of energy - there's no
"conversion" happening. It's like saying, "water can be turned into a
liquid" - no, water /is/ a liquid.
...
On 1/1/26 08:19, Stefan Ram wrote:
"Paul.B.Andersen" <relativity@paulba.no> wrote or quoted:
:that mass could be converted to energy as
:predicted by Einstein's E = mc-#.
I can spot three mistakes here right off the bat.
First, the phrase "mass could be converted to energy" is based on
a misconception, since mass already /is/ a form of energy - there's no
"conversion" happening. It's like saying, "water can be turned into a
liquid" - no, water /is/ a liquid.
The basic problem is that you think that 'science' is
'automatically true' [...]
"Paul.B.Andersen" <relativity@paulba.no> wrote or quoted:
:that mass could be converted to energy as
:predicted by Einstein's E = mc-#.
I can spot three mistakes here right off the bat.
First, the phrase "mass could be converted to energy" is based on
a misconception, since mass already /is/ a form of energy - there's no
"conversion" happening. It's like saying, "water can be turned into a
liquid" - no, water /is/ a liquid.
Second, "E=mc^2" only applies to systems at rest. In general,
it's "E^2=(mc^2)^2+(pc)^2", where "p" is the system's momentum.
(That basically says mass is the magnitude of the four-momentum.)
Third, mass is conserved in nuclear fission. This point is often
explained incorrectly, even in otherwise solid textbooks like Grif-
fiths.
Note that m = 3.089167695E-28 kg is the _lost_ mass,
it doesn't exist any more.
So where has it gone?
It is converted to E = mc-# ree 2.776404839E-11 J of _kinetic energy_. Kinetic energy is not mass. Thus "convert".
Second, "E=mc^2" only applies to systems at rest. In general,
it's "E^2=(mc^2)^2+(pc)^2", where "p" is the system's momentum.
(That basically says mass is the magnitude of the four-momentum.)
E = mc-# is the energy content, or the energy equivalent of
the mass m.
Mass is invariant, so this equation is valid for all speeds of the mass.
However, the _total_ energy of a moving mass is:
E = m+|c-# = mc-# + (+|-1)mc-#
The first term mc-# is the invariant energy content of the mass m,
the second term is the kinetic energy of the mass m.
Kinetic energy is not mass!
Third, mass is conserved in nuclear fission. This point is often
explained incorrectly, even in otherwise solid textbooks like Grif-
fiths.
Could it be that you are wrong and the textbook is right? :-D
Before the fission the mass of the U-235 nucleus + 1 neutron
is: mreU = 3.919748214E-25 kg
After the fission the mass of the Ba-141 and Kr-92 nuclei + 3 neutrons
is: mree = 3.916659047E-25 kg.
So the mass isn't conserved,
m = mreU-mree= 3.089167695E-28 kg has disappeared because it is converted to kinetic energy which is not mass.
Den 01.01.2026 17:19, skrev Stefan Ram:
"Paul.B.Andersen" <relativity@paulba.no> wrote or quoted:
:that mass could be converted to energy as
:predicted by Einstein's E = mc-#.
I resent very much that you:
1. Break threads so it is impossible to see to what you are responding.
2. Paraphrase and not quote.
I can guess that you were responding to my statement:
-a"The atom bomb proved in a very convincing way
-a that mass could be converted to energy as
-a predicted by Einstein's E = mc-#."
This statement isn't very precise, but not wrong.
So let's look at a more precise statement about
what is happening in an atomic fission bomb:
One possible fission process is:
1n + U-235 raA Ba-141 + Kr-92 + 3n
The atomic weight (mass) of these are:
Left side:
1n-a-a-a-a-a 1.008664-a u
U-235 235.0439299 u
-------------------
-a-a-a-a-a 236.0525939 u = 3.919748214E-25 kg
Right side:
Ba-141-a-a 140.914412 u
Kr-92-a-a-a-a 91.926156 u
3n-a-a-a-a-a-a-a-a 3.025992 u
---------------------
-a-a-a-a-a-a-a-a 235.866560 u = 3.916659047E-25 kg
Lost mass: m = 0.1860339 u = 3.089167695E-28 kg
E = mc-# ree 2.776404839E-11 J
-a-a I can spot three mistakes here right off the bat.
-a-a-a-a-a-a-a First, the phrase "mass could be converted to energy" is based on
-a-a a misconception, since mass already /is/ a form of energy - there's no >> -a-a "conversion" happening. It's like saying, "water can be turned into a >> -a-a liquid" - no, water /is/ a liquid.
Note that m = 3.089167695E-28 kg is the _lost_ mass,
it doesn't exist any more.
So where has it gone?
It is converted to E = mc-# ree 2.776404839E-11 J of _kinetic energy_. Kinetic energy is not mass. Thus "convert".
-a-a-a-a-a-a-a Second, "E=mc^2" only applies to systems at rest. In general, >> -a-a it's "E^2=(mc^2)^2+(pc)^2", where "p" is the system's momentum.
-a-a (That basically says mass is the magnitude of the four-momentum.)
E = mc-# is the energy content, or the energy equivalent of
the mass m. Mass is invariant, so this equation is valid for
all speeds of the mass.
Am Sonntag000004, 04.01.2026 um 20:51 schrieb Paul.B.Andersen:
E = mc-# is the energy content, or the energy equivalent of
the mass m. Mass is invariant, so this equation is valid for
all speeds of the mass.
You contradicted yourself!!
Here your claim is, that mass is invariant, while a little below you
claim, that energy is conserved, while mass has vanished from a
radioactive sample.
But you can't keep both claims, because they contradict each other.
Den 06.01.2026 09:15, skrev Thomas Heger:
Am Sonntag000004, 04.01.2026 um 20:51 schrieb Paul.B.Andersen:
E = mc-# is the energy content, or the energy equivalent of
the mass m. Mass is invariant, so this equation is valid for
all speeds of the mass.
You contradicted yourself!!
Here your claim is, that mass is invariant, while a little below you
claim, that energy is conserved, while mass has vanished from a
radioactive sample.
But you can't keep both claims, because they contradict each other.
Invariant means "the same in all frames of reference"
or "independent of speed".
Den 06.01.2026 09:15, skrev Thomas Heger:
Am Sonntag000004, 04.01.2026 um 20:51 schrieb Paul.B.Andersen:
E = mc-# is the energy content, or the energy equivalent of
the mass m. Mass is invariant, so this equation is valid for
all speeds of the mass.
You contradicted yourself!!
Here your claim is, that mass is invariant, while a little below you
claim, that energy is conserved, while mass has vanished from a
radioactive sample.
But you can't keep both claims, because they contradict each other.
Invariant means "the same in all frames of reference"
or "independent of speed".
It does _not_ mean "constant".
Mass is invariant.
The mass of an object is the same in all frames of reference.
The mass of an object does not depend on the speed of the object.
But mass can change. Heat the object, and its mass will increase,
I have told you before, but I know you will not learn.
You never do.
On 1/6/2026 1:57 PM, Paul.B.Andersen wrote:
Den 06.01.2026 09:15, skrev Thomas Heger:
Am Sonntag000004, 04.01.2026 um 20:51 schrieb Paul.B.Andersen:
E = mc-# is the energy content, or the energy equivalent of
the mass m. Mass is invariant, so this equation is valid for
all speeds of the mass.
You contradicted yourself!!
Here your claim is, that mass is invariant, while a little below you
claim, that energy is conserved, while mass has vanished from a
radioactive sample.
But you can't keep both claims, because they contradict each other.
Invariant means "the same in all frames of reference"
or "independent of speed".
It does _not_ mean "constant".
Mass is invariant.
The mass of an object is the same in all frames of reference.
The mass of an object does not depend on the speed of the object.
But mass can change. Heat the object, and its mass will increase,
I have told you before, but I know you will not learn.
You never do.
Its odd to think of a cup of water as the water evaporates. The cup is
an object with its own mass. But, now its holding water. So, the cup "weighs" more in a sense... But, as the water evaporates, that weight
will go back to the weight of the original cup...
Think of two equal mass cups on a scale. They balance. Add water to one,
its not balanced. However, the water will evaporate and the scale shall
go back to balanced over time?
Its odd to think of a cup of water as the water evaporates. The cup is
an object with its own mass. But, now its holding water. So, the cup "weighs" more in a sense...
But, as the water evaporates, that weight will go back to the weight of
the original cup...
Think of two equal mass cups on a scale. They balance. Add water to one,
its not balanced. However, the water will evaporate and the scale shall
go back to balanced over time?
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