Science and Reason
in Hampton Roads
Dustup At The mc2 Corral!
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To commemorate the 100th Anniversary of Albert Einstein's famous
paper first describing the equivalence of energy and matter (E =
mc2), our
local paper, the Virginian Pilot (Norfolk, VA), on October 9, 2005,
ran two articles about the incredible significance of this
discovery. Click  to read
the main Virginian Pilot article, and to read
the second article.
The two articles, by Professor Brian Greene, a substantial scholar
of nuclear physics, and a major advocate and popularizer of "string
theory", set forth what was to many, a completely radical and
alarming claim, that the energy released in purely chemical
reactions (eg., running an auto, discharging a battery) is due to
small amounts of mass being converted into energy. This
completely contradicts what almost all of us learned as scientists,
and strong criticism followed. Click to read
the outraged replies to Professor Greene's articles.
One calmer reader got it mostly right, but still somewhat
wrong (click ).
In actuality, all the products of the burned log DO weigh
slightly less than the original log, but the weight loss is far too
small to weigh directly. Professor Anthony
Zee writes popular books about theoretical physics
and was speaking symbolically in the "burning log" example.
Finally, two Old Dominion University (Norfolk, VA) professors pretty
much nailed the controversy down (click ), and it surprised and disturbed most everyone.
The straight skinny is this: in all reactions: nuclear, chemical,
electrical, etc. the number of particles involved are absolutely
conserved, ie., you always end up with the same number of particles
(protons and neutrons, or in chemical reactions, electrons) before
and after the reaction. But, the particles involved are
distributed differently after the reaction. Eg., in a nuclear
fission reaction, a big uranium nucleus breaks into two smaller
nuclei and gives off some extra neutrons. If you add up all
the particles, you still have the same number of protons, neutrons,
and electrons before and after. But the difference is that
those protons, neutrons, and electrons are all arranged differently
in the final products than they were in the original starting
materials. You started with a big, heavy, high-energy uranium
nucleus, and you ended up with two smaller, lighter, lower-energy
nuclei plus a couple of scattered neutrons. Similarly, in
chemical reactions (like the burning log), you started out with a
big, heavy log with the electrons in high-energy, complicated
orbitals and you ended up with smaller, lighter, ash, cinder, and
"glowing hot gas" molecules with the electrons in lower-energy,
simple orbitals (no neutrons or protons are involved in chemical
reactions).
Now, let's look at Einstein's equation the way he wrote it in his
original 1905 paper:
We can now clearly see that the mass of a particle is dependent on
its energy. If the E of a particle gets smaller, then the m
of the particle gets smaller too. Here's the surprise that
caught so many readers off-guard: the protons and neutrons in the
smaller, simpler, lower-energy fission products weigh less than
those same particles in the big uranium nucleus; the electrons in
the simple, lower-energy ash, cinder, and gas molecules weigh less
than those same electrons in the big log.
So there's the astounding, mind-bending truth: in any reaction,
particles are always conserved, but they are re-arranged from
high-energy structures into lower-energy structures. The
same particles in lower-energy structures (through m =
E /c2) have
less mass than they had before the reaction; this decrease in mass
produces the energy (through E = mc2) of the
reaction. In
nuclear reactions, this mass change is large, large enough to be
measured directly, and produces incredible amounts of energy (in fact,
atom-bomb amounts of energy). In chemical reactions, the mass
change is much, much smaller, far too small to be measured directly,
and produces only the thermodynamic (Gibb's Free Energy, Enthalpy,
Helmholtz Free Energy, Internal Energy, etc.,) amounts of energy we
are familiar with.
The whole matter was summed up very succinctly by Dr. Larry Weinstein
of the ODU Physics Department:
"You cannot destroy electrons and you cannot destroy nucleons
(protons plus neutrons). All reactions do is to rearrange
them. A nuclear reaction rearranges protons and neutrons, and
their mass changes by about 0.1%. A chemical reaction
rearranges electrons, and their mass changes only by about
0.0000001%. It is the mass change that comes out as the
energy of the reaction."
And that's the paradigm-wrenching truth. Comfort yourself
with the words of the noted English scientist J.B.S. Haldane: "The
universe is not only stranger than we imagine, it is stranger than
we CAN imagine."
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