Late afternoon. You are observing a storm
coming in from the southwest and heading down passed Passé-a-Grill and the where
you ate at the Sea Horse. The waitresses said that the Monday of the storm they
were closed because water was up two to three inches above the floor. One said
that these storms were about one a year, that is, bad enough to close the
restaurant. A week and a couple days later you would never know the storm
happened; the place was clean and old Florida as usual. Kim, Paul and the boys
are down at the pool. Carol is washing clothes. Tomorrow it is supposed to rain
in the morning. You are meeting Bill and Jen at the Columbia for lunch. Kim and
Paul were surprised at the Sea Horse and have decided it is now are regular
stop when visiting. You and Carol are happy with their choice.
1720 hours. The storm has passed out in
the Gulf and is heading down towards Sarasota and points in between unless, of
course, it dissipates. Doug sent me a reference to this site “Space” earlier
today. I think this is very interesting – it causes me to wonder what science
will do with this in the next hundred years? We never know where a new road in
science will take us. Reality is interesting, no doubt about it.
** **
SPACE Jun 15, 2016 03:26
PM ET
Smashing
Black Holes Make Gravitational Waves, Again
The
LIGO gravitational wave detector has witnessed two small black holes collide
and merge as one, confirming that the original gravitational wave discovery was
no fluke.
Posted
by Ian O’Neill
Only
months after the historic
discovery of gravitational waves, physicists have done it again!
LIGO has detected ANOTHER black hole collision and confirmed the first
gravitational wave detection wasn't a one-off.
On
Dec. 26, the extremely faint spacetime ripples washed through our planet and
the Laser Interferometer Gravitational-wave Observatory, or LIGO, was
listening. The US-based detector recorded the distinctive gravitational wave
"chirp", meaning that, once again, we were witness to a collision of
cataclysmic proportions.
These
ripples in spacetime were first theorized by Albert Einstein over 100 years ago
when he formulated his theory of general relativity , but it's only now that
humanity has the tools to actually prove they exist. And this most recent
detection is a firm confirmation that, once again, Einstein was right.
In
a galaxy, some 1.4 billion light-years away, two small black holes got stuck in
an inescapable gravitational spiral. Their fate was sealed; they fell closer
and closer until they rapidly span around one another, colliding and merging as
one. Like the first historic detection of gravitational waves in September,
this most recent signal originated from a black hole merger, an event that
shines a previously unattainable light on one of the most violent collisions in
the universe.
With
stunning clarity, LIGO was able to “listen in" on the moments before a
black hole binary system (two black holes orbiting one another) merged as one,
producing a gravitational wave signal that was so clear, so in keeping with our
theoretical models, there was little room for speculation. LIGO had witnessed a powerful black
hole “re-birthing" that occurred around 1.3 billion years ago.
Gravitational
waves have always been there and always will be, washing through our planet
(indeed, washing through us), but only now do we know how to find them. We've
now opened our eyes to a different kind of cosmic signal — the vibrations
caused by the most energetic events known — and we are therefore witnessing the
birth of a brand new field of astronomy.
“We
can now hear the universe," said LIGO physicist and spokesperson Gabriela
Gonzalez during Thursday's triumphant meeting. “The detection is the beginning
of a new era: The field of gravitational astronomy is now a reality."
Our
place in the universe has changed profoundly and this discovery's impact could
be as transformative as the discovery of radio waves or the realization that
the universe is expanding.
Making Robust Theories Even Stronger
Trying
to explain what gravitational waves are and why they're so important is almost
as complex as the equations that describe them, but finding them not only
strengthens Einstein's already robust theories as to the nature of spacetime;
we now have a tool that can probe into a layer of the universe that was once
invisible to us. We can now sample the spacetime ripples generated by some of
the most energetic events that occur in the universe and, perhaps, use
gravitational waves to reveal new physics and discover new astrophysical phenomena.
“Now
we have proven that we have the technology to go after and detect gravitational
waves, this opens up many possibilities," Luis Lehner, of the
Perimeter Institute for Theoretical Physics, Ontario, told me during
an interview soon after Thursday's announcement.
Lehner's
research focuses on compact objects (such as black holes) that generate
powerful gravitational waves. Though not affiliated with the LIGO
collaboration, Lehner was quick to realize the ramifications of this historic
discovery. “This signal couldn't be better," he said.
LIGO would be a success, telling the
BBC: “We are there; we are in
the ball park now. It's clear that this is going to be pulled off." And
sure enough, within days of the upgrade, a surge of gravitational waves rippled
through our planet and LIGO was at last sensitive enough to observe them.
This
binary black hole merger isn't thought to be particularly special in its own
right; it is calculated that these kinds of events happen once every 15 minutes
somewhere in the universe. But this merger happened in the right place (1.3
billion light-years away) at the right time (1.3 billion years ago) for LIGO to
be listening. It was a clear signal from the universe that Einstein got it
right and his gravitational waves were real, revealing a cosmic event that
unleashed a peak power 50 times the power output of all the stars in the
universe combined. This huge blast of gravitational wave energy was recorded as
a high-frequency “chirp" by LIGO as the black holes rapidly spiraled into
one another, merging as one.
To
confirm the propagation of gravitational waves, LIGO is comprised of 2
observing stations, one in Louisiana and the other in Washington. To rule out
false positives, a candidate gravitational wave signal needs to be detected by
both stations. And the Sept. 14 event was detected first in Louisiana and then
7 milliseconds later in Washington. The signals matched and, through
triangulation, physicists were able to learn that it originated in Southern
Hemisphere skies.
Gravitational Waves — What Are They
Good For?
So
we have a confirmed black hole merger signal, what now? This discovery is
historic, that much is clear — one hundred years ago, Einstein wouldn't have
dreamed that these waves would be detectable, but here they are.
ANALYSIS:
Colliding Black Holes and the Dawn of Gravitational Astronomy
General
relativity was is one of the most profound scientific and philosophical
realizations of the 20th Century and it forms the basis of some of our most
intellectual investigations into reality itself. Astronomically, the
applications of general relativity are clear; from
gravitational lensing to measuring the expansion of the universe.
But what's not so clear are the everyday applications of Einstein's theories,
but much of today's technology uses lessons from general relativity and things
we take for granted. Take, for example, global positioning satellites: they
wouldn't be the precise tools that they are if simple corrections for time
dilation (a general relativity prediction) weren't considered.
It's
clear that general relativity has real-world applications, but when Einstein
presented his new theory in 1916, it's highly doubtful that any application
would have seemed obvious. He was simply piecing together the universe as he
saw it and general relativity was born. So now another component of general
relativity has been proven, how might gravitational waves be used? Well,
astrophysicists and cosmologists are obviously thrilled.
“Once
we've collected data from pairs of black holes, they will be like lighthouses
scattered through the universe," said theoretical physicist Neil Turok,
Perimeter Institute Director, in a video presentation on Thursday. “We will be
able to measure the rate the universe is expanding, or how much dark energy
there is in the universe to extraordinary precision, far, far greater than what
we can do today.
“Einstein
developed his theory with some clues from Nature but made basically on the
grounds of logical consistency. One hundred years later you're seeing its
predictions confirmed at exquisite precision."
ANALYSIS:
Gravitational Waves vs. Gravity Waves: Know the Difference!
What's
more, the Sept. 14 event has some peculiarities physicists are looking forward
to investigating. For example, Lehner pointed out that from analysis of the
gravitational wave signal, the “spin" or angular momentum of the merged
black hole can be measured. “If you've worked on the theory for long enough,
you'll know that spin the black hole has is very, very peculiar," he said.
For
some reason, the final spin of the black hole is slower than expected,
indicating that the two black holes collided at a low speed, or they were in a
collision configuration that caused their combined angular momentum to
counteract each other. “That is very curious; why would nature do that?"
said Lehner.
This
early puzzle could be down to some basic physics that hasn't been considered,
but more excitingly it could reveal some “new" or exotic physics that is
interfering with the predictions of general relativity. And this highlights
another use for gravitational waves: as they are generated by strong gravity
phenomena, we have a means to probe these environments from afar, perhaps
turning up some surprises along the way. Also, we might combine observations of
astrophysical phenomena with the electromagnetic signals to add more dimensions
to our understanding of what makes our universe tick.
An Application?
Naturally,
when huge announcements are made of complex scientific discoveries, many people
outside of the scientific community ask how it affects them. The profundity can
be easily missed and this is definitely the case when it comes to gravitational
waves. But consider this: When X-rays were revealed by Wilhelm Roentgen in 1895
during his experiments on cathode ray tubes, few would have known that in only
a few years these high-energy electromagnetic waves would become a key
component in everyday medicine from diagnosis to treatment. Likewise, the first
experimental production of radio waves in 1887 by Heinrich Hertz confirmed
predictions by James Clerk Maxwell's famous electromagnetic equations. Only
years later, in the 1890′s, a series of demonstrations by Guglielmo Marconi,
who set up radio transmitters and receivers, proved they had a practical use. Also,
Schrodinger's equations describing the unfathomable world of quantum dynamics
are finding an application right now in the development of super-fast quantum
computing.
All
scientific discoveries are profound and many eventually have everyday
applications that we take for granted. For now, the practical applications of
gravitational waves may seem restricted to astrophysics and cosmology — we now
have a window into a “dark universe" where no electromagnetic radiation is
required. There is little doubt in my mind that scientists and engineers will
find other uses for these spacetime ripples besides the awesome application of
probing spacetime. That said, to detect these waves in the first place huge
advances in optical engineering had to be performed by LIGO that will
inevitably spawn new technologies.
100 Years of
General Relativity: Thought and Action
Ultimately,
the detection of gravitational waves is a triumph for humanity that will
continue to teach us new things about our universe for generations to come.
This is most definitely a golden age for science, where historic discoveries
are commonplace. These discoveries drive our culture forward, making us all
richer and more aware that our universe is a beautiful and complex place. And
we know we have the intellectual capability to create models of how we think
the universe works and then perform experiments to prove we are right.
But
for me, I'm most excited to see the first “live" gravitational maps of the
cosmos, where the periodic humming of neutron stars orbiting one another and
the impulsive eruptions of supernovas are plotted, revealing a new universe, a
universe humming with ripples in spacetime.
Selected
and edited from -- http://www.seeker.com/weve-detected-gravitational-waves-so-what-1770880745.html
** **
Post. - Amorella
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