[Marxism] Is dark matter carcinogenic?

Louis Proyect lnp3 at panix.com
Tue Apr 21 19:30:33 MDT 2015


NY Times, Apr. 21 2015
Dark Matter’s Deep Reach
by George Johnson

Earlier this year, Dr. Sabine Hossenfelder, a theoretical physicist in 
Stockholm, made the jarring suggestion that dark matter might cause 
cancer. She was not talking about the “dark matter” of the genome 
(another term for junk DNA) but about the hypothetical, lightless 
particles that cosmologists believe pervade the universe and hold the 
galaxies together.

Though it has yet to be directly detected, dark matter is presumed to 
exist because we can see the effects of its gravity. As its invisible 
particles pass through our bodies, they could be mutating DNA, the 
theory goes, adding at an extremely low level to the overall rate of cancer.

It was unsettling to see two such seemingly different realms, cosmology 
and oncology, suddenly juxtaposed. But that was just the beginning. 
Shortly after Dr. Hossenfelder broached her idea in an online essay, 
Michael Rampino, a professor at New York University, added geology and 
paleontology to the picture.

Dark matter, he proposed in an article for the Royal Astronomical 
Society, is responsible for the mass extinctions that have periodically 
swept Earth, including the one that killed the dinosaurs.

His idea is based on speculations by other scientists that the Milky Way 
is sliced horizontally through its center by a thin disk of dark matter. 
As the sun, traveling around the galaxy, bobs up and down through this 
darkling plane, it generates gravitational ripples strong enough to 
dislodge distant comets from their orbits, sending them hurtling toward 
Earth.

An earlier version of this hypothesis was put forth last year by the 
Harvard physicists Lisa Randall and Matthew Reece. But Dr. Rampino has 
added another twist: During Earth’s galactic voyage, dark matter 
accumulates in its core. There the particles self-destruct, generating 
enough heat to cause deadly volcanic eruptions. Struck from above and 
below, the dinosaurs succumbed.

It is surprising to see something as abstract as dark matter take on so 
much solidity, at least in the human mind. The idea was invented in the 
early 1930s as a theoretical contrivance — a means of explaining 
observations that otherwise didn’t make sense.

Galaxies appear to be rotating so fast that they should have spun apart 
long ago, throwing off stars like sparks from a Fourth of July pinwheel. 
There just isn’t enough gravity to hold a galaxy together, unless you 
assume that it hides a huge amount of unseen matter — particles that 
neither emit or absorb light.

Some mavericks propose alternatives, attempting to tweak the equations 
of gravity to account for what seems like missing mass. But for most 
cosmologists, the idea of unseeable matter has become so deeply 
ingrained that it has become almost impossible to do without it.

Said to be five times more abundant than the stuff we can see, dark 
matter is a crucial component of the theory behind gravitational 
lensing, in which large masses like galaxies can bend light beams and 
cause stars to appear in unexpected parts of the sky.

That was the explanation for the spectacular observation of an “Einstein 
Cross” reported last month. Acting like an enormous lens, a cluster of 
galaxies deflected the light of a supernova into four images — a 
cosmological mirage. The light for each reflection followed a different 
path, providing glimpses of four different moments of the explosion.

But not even a galactic cluster exerts enough gravity to bend light so 
severely unless you postulate that most of its mass consists of 
hypothetical dark matter. In fact, astronomers are so sure that dark 
matter exists that they have embraced gravitational lensing as a tool to 
map its extent.

Dark matter, in other words, is used to explain gravitational lensing, 
and gravitational lensing is taken as more evidence for dark matter.

Some skeptics have wondered if this is a modern-day version of what 
ancient astronomers called “saving the phenomena.” With enough 
elaborations, a theory can account for what we see without necessarily 
describing reality. The classic example is the geocentric model of the 
heavens that Ptolemy laid out in the Almagest, with the planets orbiting 
Earth along paths of complex curlicues.

Ptolemy apparently didn’t care whether his filigrees were real. What was 
important to him was that his model worked, predicting planetary 
movements with great precision.

Modern scientists are not ready to settle for such subterfuge. To show 
that dark matter resides in the world and not just in their equations, 
they are trying to detect it directly.

Though its identity remains unknown, most theorists are betting that 
dark matter consists of WIMPs — weakly interacting massive particles. If 
they really exist, it might be possible to glimpse them when they 
interact with ordinary matter.

Based on that hope, scientists have constructed underground detectors 
attempting to measure the impact of the particles as they fly through 
Earth and occasionally collide with atoms of xenon, argon or some other 
substance. But so far, there have been no hits.

Somewhere from 10 to a few thousand times a year, Dr. Hossenfelder 
estimated, a WIMP may happen to strike one of our own atoms, including 
some that make up DNA. The energy would be strong enough to break 
molecular bonds and cause mutations.

When it comes to cancer, that is a negligible threat. Two of Dr. 
Hossenfelder’s colleagues, Katherine Freese and Christopher Savage, 
estimate that cosmic rays zipping through a human body cause more damage 
in a second than dark matter would in a lifetime. But the effect of dark 
matter is still strong enough that scientists are considering using DNA 
or RNA molecules as WIMP detectors.

If WIMPs turn out to be a fiction, something else will have to be found 
to explain all of the missing mass. Something is screwy about the 
universe, and astronomers are determined to find out why.



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