A Constant Constant?
A few days ago I saw a news item stating that NASA has found
the cause of the detached foam that resulted in the Columbia
shuttle disaster. It seems there were voids between the foam and
the rocket body to which it was attached. Leakage of either
liquid nitrogen or hydrogen, I forget which, into these voids, and
the subsequent expansion of the liquefied gas, is thought to have
led to an explosive detachment of the foam. Let’s hope that the
process for applying the foam can be improved and the shuttle
flights resumed. One future flight that has been canceled was to
have serviced the Hubble Space Telescope in 2006.
After President Bush announced the proposed manned mission to
Mars, NASA decided to cancel the servicing flight and sacrifice
the Hubble. Like many others, I’m very disappointed that the
quest for Mars has doomed the Hubble Space Telescope to an
early demise. However, I was heartened to read in a news item
by Andrew Lawler in the February 6 issue of Science that
Senator Barbara Mikulski has won a review of the decision.
Harold Gehman, leader of the investigation into the Columbia
Space shuttle disaster, will carry out the review.
Our editor, Brian Trumbore, sent me a couple of items from the
February 21 editions of the Washington Post and the New York
Times on some very important recent results reported by workers
employing the Hubble telescope. The Hubble data seem to
confirm once again that Albert Einstein, even when he
“blundered”, was right on the money. We’ve talked before about
his so-called “cosmological constant” but let’s revisit it to set the
stage for these recent findings. When Einstein proposed this
cosmological constant, it was thought that the universe was a
static place. Einstein was concerned that, with all those stars out
there, gravity should take over and the attraction among all the
celestial bodies should result in the collapse of the universe.
So, what was keeping these bodies apart? Einstein’s reasoned
that since the universe was not collapsing, there must be some
kind of force pushing it apart just enough to keep it stable.
Therefore, he introduced into his equations a fudge factor, his
cosmological constant, which represented a force that pushes
against the gravitational force pulling things together. Einstein
suggested that this cosmological force was essentially unchanged
throughout the history of the universe. This was back in 1917
when the universe was a static place.
But in 1929 Edwin Hubble showed that, far from being static, the
universe was expanding and the Big Bang explanation followed.
Einstein decided that his cosmological constant was not needed
and called it his greatest blunder. Then, just a few years ago,
came evidence that not only is the universe expanding but also
that the expansion is speeding up. We began hearing about “dark
energy”, something working against gravity pushing things apart.
The cosmological constant was back and Einstein’s “blunder”
was far from a blunder. We’ve been over this road before, so
what’s new that requires further consideration?
Remember that Einstein suggested that the cosmological constant
was unchanged throughout the history of the universe. Now,
with the rebirth of the constant, the question became “Was
Einstein right, has the cosmological constant been truly constant
or is it changing?” The recent work of Adam Reiss and his
coworkers at the Space Telescope Science Institute in Baltimore
and at the University of California at Berkeley provides data
related to this question. They used the Hubble Space Telescope
to look for supernovae, exploding stars. According to the Times
article, by James Glanz, they found 42 new supernovae. Some of
these were among the most distant supernovae ever seen, dating
two-thirds of the way back to the Big Bang.
According to the Post article, by Rob Stein, 16 of these
supernovae were studied in detail insofar as the properties of the
light they emitted is concerned. It is from such studies that the
existence of dark energy was found. Since the light emitted by
these supernovae originated over a wide range of times in the
past, it is possible to calculate whether the cosmological constant
varied over billions of light years. Why concern ourselves with
how this cosmological constant varies?
It makes a big difference in our future, or at least the future of
our universe. If the cosmological constant is increasing over
time, it might become so strong that we have a “Big Rip”, in
which galaxies and stars and maybe even atoms are eventually
ripped apart. On the other hand, if the cosmological constant is
decreasing, the universe may stop expanding and end up
collapsing in a “Big Crunch”.
Einstein’s hunch was that the constant was indeed constant. Sure
enough, the Hubble telescope data gathered so far makes it look
like Einstein was right. The cosmological constant seems not to
have varied much if at all over time. If this conclusion is correct,
it looks like our universe will just keep expanding forever. If
there is still an Earth, its sky will grow darker and darker until
nothing is visible. It will be a cold and lonely place.
Naturally, astronomers will be anxiously searching for more
supernovae to check these first results. Obviously, the demise of
the Hubble telescope clouds the outlook for any prolonged effort
along these lines. It’s no wonder that Senator Mikulski got a
standing ovation when she appeared in Baltimore at the
aforementioned Space Telescope Science Institute after the
decision to reevaluate the Hubble situation. Considering the
terrible start of the Hubble mission caused by the improper
grinding of the telescopes lens and then the Shuttle mission to
correct the problem, it’s amazing how that instrument has
changed our view of our universe.
As I’m typing this I look out on our little bay and the fishermen
going out in their boats. Fishing requires a lot of patience.
Perhaps we should be more patient in our quest for a manned trip
to Mars and allow the Hubble to continue to fish the universe for
supernovae and all sorts of other oddities that will amaze and
Totally unrelated to science, patience is something that our
nephew Bob needed recently when we went out to a nearby golf
course. It was the first time I’ve been golfing since my kidney
surgery last September. Bob had to bide his time while I plunked
no fewer than a dozen golf balls in the numerous bodies of water
that decorated the course. My score was indeterminate, what
with picking up on a hole or two and finding it difficult to
remember the large number of strokes on any given hole.
Later, my wife and I joined Bob and his wife Brenda on a trip up
to what must be the biggest flea market in the world in Ft. Myers.
Normally, I detest any kind of shopping. However, I managed to
purchase 50 pre-owned golf balls for the paltry sum of $7.55 and
a 2-metal for $25. I figure that the 2-metal might replace my
borrowed driver, the face of which seems to have a negative
slope based on the trajectory of my drives into the water. And 50
golf balls should suffice for at least a couple of rounds. If not, I
will probably give up the game forever!
Finally, a few words about birds of the non-golfing variety.
Yesterday, I counted no less than 26 pelicans gathered around a
fisherman cleaning his catch on the marina outside our condo. I
can report that the pelican is not an endangered species. I’m not
sure about the status of the muscovy duck but it seems to have an
appreciation for Cole Porter. The Naples Concert Band gave a
concert in the park here on Marco Island and during a melody of
Cole Porter tunes, this quite large duck flies up on the basket
(basketball) bordering the covered shelter housing the band and
audience. The duck, silhouetted against the sky, stayed for the
Porter medley, swaying its head in time with the music. It joins
the heron that I’ve reported standing at the water’s edge at 6 AM
looking at the moon as one of those birds that I fantasize
appreciates the finer things in life.
Allen F. Bortrum