The world of physics was abuzz last week with
the historic
announcement of the first-ever detection of
gravitational waves. But
why is it such a big deal?
By Sabrina Stierwalt, PhD. on February 24,
2016


Last week marked the historic announcement
of the first detection of
gravitational waves. A big press conference
was held, and physicists
around the world celebrated. The discovery
was even compared to
Galileo looking through a telescope for the
first time. So why all the
fanfare? Why are gravitational waves such a
huge deal?
Last week marked the historic announcement
of the first detection of
gravitational waves. A big press conference
was held, and physicists
around the world celebrated. The discovery
was even compared to
Galileo looking through a telescope for the
first time. So why all the
fanfare? Why are gravitational waves such a
huge deal?


1. GRAVITATIONAL WAVES ARE AN ENTIRELY
NEW WAY
OF OBSERVING THE UNIVERSE


Astronomers observe the universe across the
electromagnetic
spectrum, from X-ray and ultraviolet through
optical and down to
radio frequencies. Emission in each of these
frequency ranges provides
different information and thus a different
perspective on our
astronomical points of interest.
For example, we know that there are millions
of stars clustered toward
the center of our Galaxy which emit mostly at
optical wavelengths, but
there is also a lot of dust near the Galactic
center as well. So to study
those dust-enshrouded stars, astronomers
must observe them at either
infrared wavelengths (where the dust emits)
or radio wavelengths
(which can penetrate through the dust more
effectively than shorter
optical wavelengths). All of these wavelengths
offer a unique
perspective on the universe, but they are all
the same kind of light,
electromagnetic radiation, and so behave in
similar, understood ways.
Gravitational waves are an entirely new
phenomenon different from
anything on the electromagnetic spectrum. In
1915, Albert Einstein
proposed a radically different way of looking
at gravity with his theory
of general relativity. Rather than thinking of
gravity as a force pushing
and pulling massive objects in different
directions, he described
gravity as being manifested in a curvature of
spacetime. In other
words, the space (and time) around a massive
object is curved, which
then dictates how passing objects can move
through that space.
This may sound crazy, but we can actually
observe many of the effects
predicted by Einstein’s theory. For example,
general relativity informs
us that time passes more slowly by an ever so
small margin down here
on Earth than it does for GPS satellites in
orbit, an effect known as
time dilation, a result of the curvature of
spacetime. Without adjusting
for this small time difference in our satellite
communications, we
would never get to where we are trying to go.
A consequence of the general relativity
framework is that when
objects accelerate through this warping of
spacetime, they produce
ripples known as gravitational waves. These
waves propagate through
space, compressing it in one direction and
stretching it in another.
The frequencies predicted for these
fluctuations are within the human
hearing range. We can hear gravitational
waves and already scientists
and artists have teamed up to explore other
artistic interpretations of
their sound.
So why did it take 100 years to detect them?
These ripples are tiny, on
order of a thousandth of the size of a proton
nucleus, so we need a
pretty violent event to occur to produce
enough of them for us to
detect. We also need, of course, a very
sensitive detector.


2. The Instrument That Made the
Gravitational Wave Detection Is
the Most Precise Measuring System Ever Built


To detect such tiny distortions in spacetime,
physicists use a technique
called laser interferometry. A focused beam
of light is sent in different
directions to bounce back and forth between
two sets of mirrors before
being sent to a detector. If a gravitational
wave passes by the
interferometer during all of this bouncing,
the distance between the
mirrors will change ever so slightly and this
change will translate to a
difference in the two signals as measured by
the detector.
Not only is the signal from gravitational waves
incredibly weak, there is
also a significant amount of competing noise
attempting to drown it out.
To increase the detectability of such a signal
against the background
noise, the path the laser travels must be a
long one. The Laser
Interferometer Gravitational-Wave
Observatory (LIGO), the instrument
that made the historic detection, is four
kilometers long on each side.
The detectors are further suspended in the
air in hopes of isolating the
slightly faster wiggles due to gravitational
waves from terrestrial
interference.
To further fight back against false
detections, LIGO has not one but two
detectors: one in Hanford, Washington and
the other in Livingston,
Louisiana. Detecting the same signal at both,
widely separated locations
would mean that signal was likely not a local
one. And that is exactly
what happened on September 14, 2015—a
signal with the precise
characteristics predicted for gravitational
waves was observed at both
detectors only milliseconds apart.


3. We Now Know That Massive Black Holes Can
Merge to Create
Even Bigger Black Holes


Famous theoretical physicist and author Kip
Thorne described the event
that produced the detected gravitational
waves as a “violent storm in the
fabric of space and time”. Around 1.3 billion
years ago, when
multicellular life was just beginning here on
Earth, two black holes
orbiting each other began to close in on one
another. As these dense
objects got closer, they began to accelerate
to nearly half the speed of
light in the presence of their shared strong
gravitational field – the
perfect mix for producing gravitational
waves.
From fitting the waveform of the
gravitational wave detection and
comparing it to simulations done with a
supercomputer, astronomers
can tell that the two black holes were
originally 29 and 36 times the
mass of our Sun. They merged to form a 62
solar mass black hole which
means that an amount three times the mass
of our Sun was emitted away
as energy in the form of gravitational waves,
all in the 20 milliseconds
it took for the collision to happen! That’s a
power output of 50 times
greater than all of the power put out by all of
the stars in the universe
put together.
Before this first detection, astronomers
were not even sure that mergers
between black holes existed, and now the
details of this particular event
are known to a high degree of certainty.


4. Hundreds of People Had to Take a Huge Risk
to Make This
Detection Possible


Einstein predicted the existence of
gravitational waves 100 years ago
but at the time, there was significant doubt
that such weak signals could
ever be detected. In 1992, LIGO became the
largest investment the
National Science Foundation had ever made.
The investment was a risky
one–the existence of gravitational waves was
only theoretical, and their
signal, even if they were real, would be
impossible to detect without the
construction of an instrument larger than
any other measurement device
previously built. In fact, the initial operations
of LIGO between 2002
and 2010 came up empty-handed.
However, when the new and improved advanced
LIGO came online with
its increased sensitivity, it detected a signal
that was so clear it could be
seen by eye almost immediately.


5. With Our New Ears on the Universe, We Will
Likely Make
Discoveries We Haven’t Even Thought of Yet


Arguably the most exciting part of this new
discovery is that it’s only
the beginning! The ease with which LIGO
detected the signal suggests
that there will be many more to come and that
we won’t have to wait
long for them either. The LIGO detectors are
not even at their full
planned sensitivity yet and so detections will
get easier.
The success of LIGO will also likely help other,
similar projects get
funded, and in fact it likely already has with
the prime minister of India
voicing support for LIGO India. Other efforts
include KAGRA in Japan,
VIRGO in Italy, and the already operational
GEO600 in Germany.
Using multiple detectors in concert will
further help pinpoint the origin
of the gravitational wave signals.
The LISA project (i.e., the Laser
Interferometer Space Antenna), which
has experienced funding woes since NASA
bowed out in 2011 and the
project was picked up entirely by European
agencies, would also send
gravitational wave detectors into space. This
would open up the
possibility of detecting signals with much
longer periods (on the order
of minutes or hours rather than milliseconds)
not currently possible
with LIGO.
Gravitational waves are predicted to arise
from co-orbiting black holes
like the system detected in September 2015,
but also from binary
systems with other compact objects like
neutron stars. But gravitational
waves are also fundamentally different from
the electromagnetic
radiation that we know so well. So really, who
knows what we will find?

cc lalasticlala seun Fynestboi

Thomsyne:
The world of physics was abuzz last week with
the historic
announcement of the first-ever detection of
gravitational waves. But
why is it such a big deal?
By Sabrina Stierwalt, PhD. on February 24,
2016


Last week marked the historic announcement
of the first detection of
gravitational waves. A big press conference
was held, and physicists
around the world celebrated. The discovery
was even compared to
Galileo looking through a telescope for the
first time. So why all the
fanfare? Why are gravitational waves such a
huge deal?
Last week marked the historic announcement
of the first detection of
gravitational waves. A big press conference
was held, and physicists
around the world celebrated. The discovery
was even compared to
Galileo looking through a telescope for the
first time. So why all the
fanfare? Why are gravitational waves such a
huge deal?


1. GRAVITATIONAL WAVES ARE AN ENTIRELY
NEW WAY
OF OBSERVING THE UNIVERSE


Astronomers observe the universe across the
electromagnetic
spectrum, from X-ray and ultraviolet through
optical and down to
radio frequencies. Emission in each of these
frequency ranges provides
different information and thus a different
perspective on our
astronomical points of interest.
For example, we know that there are millions
of stars clustered toward
the center of our Galaxy which emit mostly at
optical wavelengths, but
there is also a lot of dust near the Galactic
center as well. So to study
those dust-enshrouded stars, astronomers
must observe them at either
infrared wavelengths (where the dust emits)
or radio wavelengths
(which can penetrate through the dust more
effectively than shorter
optical wavelengths). All of these wavelengths
offer a unique
perspective on the universe, but they are all
the same kind of light,
electromagnetic radiation, and so behave in
similar, understood ways.
Gravitational waves are an entirely new
phenomenon different from
anything on the electromagnetic spectrum. In
1915, Albert Einstein
proposed a radically different way of looking
at gravity with his theory
of general relativity. Rather than thinking of
gravity as a force pushing
and pulling massive objects in different
directions, he described
gravity as being manifested in a curvature of
spacetime. In other
words, the space (and time) around a massive
object is curved, which
then dictates how passing objects can move
through that space.
This may sound crazy, but we can actually
observe many of the effects
predicted by Einstein’s theory. For example,
general relativity informs
us that time passes more slowly by an ever so
small margin down here
on Earth than it does for GPS satellites in
orbit, an effect known as
time dilation, a result of the curvature of
spacetime. Without adjusting
for this small time difference in our satellite
communications, we
would never get to where we are trying to go.
A consequence of the general relativity
framework is that when
objects accelerate through this warping of
spacetime, they produce
ripples known as gravitational waves. These
waves propagate through
space, compressing it in one direction and
stretching it in another.
The frequencies predicted for these
fluctuations are within the human
hearing range. We can hear gravitational
waves and already scientists
and artists have teamed up to explore other
artistic interpretations of
their sound.
So why did it take 100 years to detect them?
These ripples are tiny, on
order of a thousandth of the size of a proton
nucleus, so we need a
pretty violent event to occur to produce
enough of them for us to
detect. We also need, of course, a very
sensitive detector.


2. The Instrument That Made the
Gravitational Wave Detection Is
the Most Precise Measuring System Ever Built


To detect such tiny distortions in spacetime,
physicists use a technique
called laser interferometry. A focused beam
of light is sent in different
directions to bounce back and forth between
two sets of mirrors before
being sent to a detector. If a gravitational
wave passes by the
interferometer during all of this bouncing,
the distance between the
mirrors will change ever so slightly and this
change will translate to a
difference in the two signals as measured by
the detector.
Not only is the signal from gravitational waves
incredibly weak, there is
also a significant amount of competing noise
attempting to drown it out.
To increase the detectability of such a signal
against the background
noise, the path the laser travels must be a
long one. The Laser
Interferometer Gravitational-Wave
Observatory (LIGO), the instrument
that made the historic detection, is four
kilometers long on each side.
The detectors are further suspended in the
air in hopes of isolating the
slightly faster wiggles due to gravitational
waves from terrestrial
interference.
To further fight back against false
detections, LIGO has not one but two
detectors: one in Hanford, Washington and
the other in Livingston,
Louisiana. Detecting the same signal at both,
widely separated locations
would mean that signal was likely not a local
one. And that is exactly
what happened on September 14, 2015—a
signal with the precise
characteristics predicted for gravitational
waves was observed at both
detectors only milliseconds apart.


3. We Now Know That Massive Black Holes Can
Merge to Create
Even Bigger Black Holes


Famous theoretical physicist and author Kip
Thorne described the event
that produced the detected gravitational
waves as a “violent storm in the
fabric of space and time”. Around 1.3 billion
years ago, when
multicellular life was just beginning here on
Earth, two black holes
orbiting each other began to close in on one
another. As these dense
objects got closer, they began to accelerate
to nearly half the speed of
light in the presence of their shared strong
gravitational field – the
perfect mix for producing gravitational
waves.
From fitting the waveform of the
gravitational wave detection and
comparing it to simulations done with a
supercomputer, astronomers
can tell that the two black holes were
originally 29 and 36 times the
mass of our Sun. They merged to form a 62
solar mass black hole which
means that an amount three times the mass
of our Sun was emitted away
as energy in the form of gravitational waves,
all in the 20 milliseconds
it took for the collision to happen! That’s a
power output of 50 times
greater than all of the power put out by all of
the stars in the universe
put together.
Before this first detection, astronomers
were not even sure that mergers
between black holes existed, and now the
details of this particular event
are known to a high degree of certainty.


4. Hundreds of People Had to Take a Huge Risk
to Make This
Detection Possible


Einstein predicted the existence of
gravitational waves 100 years ago
but at the time, there was significant doubt
that such weak signals could
ever be detected. In 1992, LIGO became the
largest investment the
National Science Foundation had ever made.
The investment was a risky
one–the existence of gravitational waves was
only theoretical, and their
signal, even if they were real, would be
impossible to detect without the
construction of an instrument larger than
any other measurement device
previously built. In fact, the initial operations
of LIGO between 2002
and 2010 came up empty-handed.
However, when the new and improved advanced
LIGO came online with
its increased sensitivity, it detected a signal
that was so clear it could be
seen by eye almost immediately.


5. With Our New Ears on the Universe, We Will
Likely Make
Discoveries We Haven’t Even Thought of Yet


Arguably the most exciting part of this new
discovery is that it’s only
the beginning! The ease with which LIGO
detected the signal suggests
that there will be many more to come and that
we won’t have to wait
long for them either. The LIGO detectors are
not even at their full
planned sensitivity yet and so detections will
get easier.
The success of LIGO will also likely help other,
similar projects get
funded, and in fact it likely already has with
the prime minister of India
voicing support for LIGO India. Other efforts
include KAGRA in Japan,
VIRGO in Italy, and the already operational
GEO600 in Germany.
Using multiple detectors in concert will
further help pinpoint the origin
of the gravitational wave signals.
The LISA project (i.e., the Laser
Interferometer Space Antenna), which
has experienced funding woes since NASA
bowed out in 2011 and the
project was picked up entirely by European
agencies, would also send
gravitational wave detectors into space. This
would open up the
possibility of detecting signals with much
longer periods (on the order
of minutes or hours rather than milliseconds)
not currently possible
with LIGO.
Gravitational waves are predicted to arise
from co-orbiting black holes
like the system detected in September 2015,
but also from binary
systems with other compact objects like
neutron stars. But gravitational
waves are also fundamentally different from
the electromagnetic
radiation that we know so well. So really, who
knows what we will find?

cc lalasticlala seun Fynestboi

So how does this affect us. How does it affect the economy of naija or the price of Naira to dollar...... Is elon musk not in South Africa with his solar and electric cars that travel almost as fast as bullets? Yet how did that make buhari even notice him or how did it change our economy. Pls pls pls post solutions here that can make nigeria have hope. Not some Abstract progress we may never experience unless we leave nigeria

We in Africa are still listening to lazy people 'prophesying' about plane crashes and who will win or lose which election. Civilized people are fulfilling the prophecies of the real men of God. Men whom God really spoke to; Copernicus, Galileo, Newton, Lavoisier, Chatelet, Faraday, Maxwell, Einstein etc.

This is a fulfillment of prophecy by Albert Einstein. More of such prophecies, including the theory of a multiverse, are expected to be fulfilled in the nearest future.

Only science can give God glory. Religion is a scam.

oglalasioux:
We in Africa are still listening to lazy people 'prophesying' about plane crashes and who will win or lose which election. Civilized people are fulfilling the prophecies of the real men of God. Men whom God really spoke to; Copernicus, Galileo, Newton, Lavoisier, Chatelet, Faraday, Maxwell, Einstein etc.

This is a fulfillment of prophecy by Albert Einstein. More of such prophecies, including the theory of a multiverse, are expected to be fulfilled in the nearest future.

Only science can give God glory. Religion is a scam.

Tell them brother

Science is God and God is science..
Religion is just like a guide line to make us reason better and behave better than animals...

oglalasioux:
We in Africa are still listening to lazy people 'prophesying' about plane crashes and who will win or lose which election. Civilized people are fulfilling the prophecies of the real men of God. Men whom God really spoke to; Copernicus, Galileo, Newton, Lavoisier, Chatelet, Faraday, Maxwell, Einstein etc.

This is a fulfillment of prophecy by Albert Einstein. More of such prophecies, including the theory of a multiverse, are expected to be fulfilled in the nearest future.

Only science can give God glory. Religion is a scam.

kini multiverse

When will the name of black enter OKEKE physics?

Chazzyboy:
kini multiverse

Google is your friend.

tripplephi:



So how does this affect us. How does it affect the economy of naija or the price of Naira to dollar...... Is elon musk not in South Africa with his solar and electric cars that travel almost as fast as bullets? Yet how did that make buhari even notice him or how did it change our economy. Pls pls pls post solutions here that can make nigeria have hope. Not some Abstract progress we may never experience unless we leave nigeria

Was that why you had to quote the entire article?

So, if a news doesn't affect your economy, you're not interested ba?

Why do you people take so much joy in being dense na?

tripplephi:



So how does this affect us. How does it affect the economy of naija or the price of Naira to dollar...... Is elon musk not in South Africa with his solar and electric cars that travel almost as fast as bullets? Yet how did that make buhari even notice him or how did it change our economy. Pls pls pls post solutions here that can make nigeria have hope. Not some Abstract progress we may never experience unless we leave nigeria

Sharrap there!

Thomsyne:


Tell them brother

Lol. Caught in the act