Showing posts with label LIGO. Show all posts
Showing posts with label LIGO. Show all posts

Wednesday, November 06, 2019

Music of the Universe



"In a special public lecture webcast at Perimeter Institute on October 23, 2019, Gabriela González will provide a first-hand account of LIGO’s century-in-the-making breakthrough, and explain observations made as recently as this year. González, a professor of physics and astronomy at Louisiana State University and former spokesperson of the LIGO collaboration, will take the audience on a journey to some of the universe’s most violent places, and explain how such distant events can lead to a very bright future here on Earth."
See: Music of the Universe: Gabriela González public lecture

Wednesday, August 22, 2018

Hey LIGO


Hey LIGO

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How’s it going, LIGO?

 Members of the public can use Hey LIGO; they just might be disappointed if they’re looking for the kind of quippy, vocalized replies we’ve come to expect from our digital assistants. Hey LIGO is more likely to spit out links to technical reports and schematics. But for researchers, that’s just fine

08/21/18
The Laser Interferometer Gravitational-Wave Observatory has a new digital assistant. Symmetry Magazine

Wednesday, June 15, 2016

Gravitational Waves detected by LIGO



See Also: LIGO again detects gravitational waves 

 The scientists detected the gravitational waves using the twin Laser Interferometer Gravitational-wave Observatory (LIGO) interferometers, located in Livingston, Louisiana, and Hanford, Washington. On Dec. 26, 2015, at 3:38 UTC, both detectors, situated more than 3,000 kilometers apart, picked up a very faint signal amid the surrounding noise..... See: For second time, LIGO detects gravitational waves, by

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SEE also:

LIGO experiment’s discovery of gravitational waves

LIGO Livingston observatory. Credit: Caltech/MIT/LIGO Lab.

Scientists from the LIGO Scientific Collaboration (LSC) and the Virgo Collaboration will discuss their latest research in the effort to detect gravitational waves, at the 228th meeting of the American Astronomical Society (AAS) in San Diego, California. The briefing is scheduled to begin at 10:15 AM Pacific Daylight Time on Wednesday, June 15th. See: WEDNESDAY: LIGO, Virgo scientists discuss continued search for gravitational waves at AAS meeting

 Interested individuals can watch the press briefing live at: https://aas.org/aas-briefing-webcast

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See Also:

Sunday, February 21, 2016

The Sound of Two Black Holes Colliding


Audio Credit: Caltech/MIT/LIGO Lab

 As the black holes spiral closer and closer in together, the frequency of the gravitational waves increases. Scientists call these sounds "chirps," because some events that generate gravitation waves would sound like a bird's chirp. See: The Sound of Two Black Holes Colliding

This is an Audio Animation above.

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The upcoming network of Earth-based detectors, comprising Advanced Virgo, KAGRA in Japan, and possibly a third LIGO detector in India, will help scientists determine the locations of sources in the sky. This would tell us where to aim “traditional” telescopes that collect electromagnetic radiation or neutrinos. Combining observational tools in this way would be the basis for a new research field, sometimes referred to as “multimessenger astronomy” [7]. Soon we will also collect the first results from LISA Pathfinder, a spacecraft experiment serving as a testbed for eLISA, a space-based interferometer. eLISA will enable us to peer deeper into the cosmos than ground-based detectors, allowing studies of the formation of more massive black holes and investigations of the strong-field behavior of gravity at cosmological distances [8].See: Viewpoint: The First Sounds of Merging Black Holes
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See Also:

Wednesday, February 17, 2016

No-Hair Theorem

The no-hair theorem postulates that all black hole solutions of the Einstein-Maxwell equations of gravitation and electromagnetism in general relativity can be completely characterized by only three externally observable classical parameters: mass, electric charge, and angular momentum.[1] All other information (for which "hair" is a metaphor) about the matter which formed a black hole or is falling into it, "disappears" behind the black-hole event horizon and is therefore permanently inaccessible to external observers. Physicist John Archibald Wheeler expressed this idea with the phrase "black holes have no hair"[1] which was the origin of the name. In a later interview, John Wheeler says that Jacob Bekenstein coined this phrase.[2]

The first version of the no-hair theorem for the simplified case of the uniqueness of the Schwarzschild metric was shown by Werner Israel in 1967.[3] The result was quickly generalized to the cases of charged or spinning black holes.[4][5] There is still no rigorous mathematical proof of a general no-hair theorem, and mathematicians refer to it as the no-hair conjecture. Even in the case of gravity alone (i.e., zero electric fields), the conjecture has only been partially resolved by results of Stephen Hawking, Brandon Carter, and David C. Robinson, under the additional hypothesis of non-degenerate event horizons and the technical, restrictive and difficult-to-justify assumption of real analyticity of the space-time continuum.

Contents

 

Example

Suppose two black holes have the same masses, electrical charges, and angular momenta, but the first black hole is made out of ordinary matter whereas the second is made out of antimatter; nevertheless, they will be completely indistinguishable to an observer outside the event horizon. None of the special particle physics pseudo-charges (i.e., the global charges baryonic number, leptonic number, etc.) are conserved in the black hole.[citation needed]

Changing the reference frame
 
Every isolated unstable black hole decays rapidly to a stable black hole; and (excepting quantum fluctuations) stable black holes can be completely described (in a Cartesian coordinate system) at any moment in time by these eleven numbers:
These numbers represent the conserved attributes of an object which can be determined from a distance by examining its gravitational and electromagnetic fields. All other variations in the black hole will either escape to infinity or be swallowed up by the black hole.
By changing the reference frame one can set the linear momentum and position to zero and orient the spin angular momentum along the positive z axis. This eliminates eight of the eleven numbers, leaving three which are independent of the reference frame. Thus any black hole which has been isolated for a significant period of time can be described by the Kerr–Newman metric in an appropriately chosen reference frame.

Four-dimensional space-time

The no-hair theorem was originally formulated for black holes within the context of a four-dimensional spacetime, obeying the Einstein field equation of general relativity with zero cosmological constant, in the presence of electromagnetic fields, or optionally other fields such as scalar fields and massive vector fields (Proca fields, spinor fields, etc.).[citation needed]

Extensions

It has since been extended to include the case where the cosmological constant is positive (which recent observations are tending to support).[6]
Magnetic charge, if detected as predicted by some theories, would form the fourth parameter possessed by a classical black hole.

Counterexamples

Counterexamples in which the theorem fails are known in spacetime dimensions higher than four; in the presence of non-abelian Yang-Mills fields, non-abelian Proca fields, some non-minimally coupled scalar fields, or skyrmions; or in some theories of gravity other than Einstein’s general relativity. However, these exceptions are often unstable solutions and/or do not lead to conserved quantum numbers so that "The 'spirit' of the no-hair conjecture, however, seems to be maintained".[7] It has been proposed that "hairy" black holes may be considered to be bound states of hairless black holes and solitons.
In 2004, the exact analytical solution of a (3+1)-dimensional spherically symmetric black hole with minimally coupled self-interacting scalar field was derived.[8] This showed that, apart from mass, electrical charge and angular momentum, black holes can carry a finite scalar charge which might be a result of interaction with cosmological scalar fields such as the inflaton. The solution is stable and does not possess any unphysical properties, however, the existence of scalar field with desired properties is only speculative.

Observational results

The LIGO results provide the first experimental observation of the uniqueness or no-hair theorem.[9][10] This observations are consistent with Stephen Hawking theoretical work on black holes in the 1970s.[11][12]

See also

References








  • Misner, Charles W.; Thorne, Kip S.; Wheeler, John Archibald (1973). Gravitation. San Francisco: W. H. Freeman. pp. 875–876. ISBN 0716703343. Retrieved 24 January 2013.
  • https://www.youtube.com/watch?v=BIHPWKXvGkE&feature=youtu.be&t=6m
  • Israel, Werner (1967). "Event Horizons in Static Vacuum Space-Times". Phys. Rev. 164 (5): 1776–1779. Bibcode:1967PhRv..164.1776I. doi:10.1103/PhysRev.164.1776.
  • Israel, Werner (1968). "Event horizons in static electrovac space-times". Commun. Math. Phys. 8 (3): 245–260. Bibcode:1968CMaPh...8..245I. doi:10.1007/BF01645859.
  • Carter, Brandon (1971). "Axisymmetric Black Hole Has Only Two Degrees of Freedom". Phys. Rev. Lett. 26 (6): 331–333. Bibcode:1971PhRvL..26..331C. doi:10.1103/PhysRevLett.26.331.
  • Bhattacharya, Sourav; Lahiri, Amitabha (2007). "No hair theorems for positive Λ". arXiv:gr-qc/0702006v2.
  • Mavromatos, N. E. (1996). "Eluding the No-Hair Conjecture for Black Holes". arXiv:gr-qc/9606008v1.
  • Zloshchastiev, Konstantin G. (2005). "Coexistence of Black Holes and a Long-Range Scalar Field in Cosmology". Phys. Rev. Lett. 94 (12): 121101. arXiv:hep-th/0408163. Bibcode:2005PhRvL..94l1101Z. doi:10.1103/PhysRevLett.94.121101.
  • "Gravitational waves from black holes detected". BBC News. 11 February 2016.
  • "Gravitational waves detected 100 years after Einstein's prediction" (PDF). LIGO. February 11, 2016. Retrieved 11 February 2016.
  • https://www.facebook.com/stephenhawking/posts/965377523549345 Stephen Hawking

    1. http://www.bbc.com/news/science-environment-35551144 Stephen Hawking celebrates gravitational wave discovery

    External links


    Categories
     




  • Black holes
  • Theorems in general relativity
  • Is Gravity Now part of the Standard Model?

    I leave this as a open question as I will be compiling information in this regard. If the initial configuration of the source is being transmitted as gravitational waves then this is also part of "other information" being traversed through space and space-time?

    Image Credit: NASA Goddard Space Flight Center.


    This in affect pertains to recent events regarding the detection of gravitational waves recent. So I have ideas about this now.

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    See:

    Wednesday, July 02, 2014

    Proofing BICEP2

    Inflation—the hypothesis that the Universe underwent a phase of superluminal expansion in a brief period following the big bang—has the potential of explaining, from first principles, why the Universe has the structure we see today. It could also solve outstanding puzzles of standard big-bang cosmology, such as why the Universe is, to a very good approximation, flat and isotropic (i.e., it looks the same in all directions). Yet we do not yet have a compelling model, based on fundamental particle physics principles, that explains inflation. And despite its explanatory power and a great deal of suggestive evidence, we still lack an unambiguous and direct probe of inflation. Theorists have developed different models for inflation, which all share a common, robust prediction: Inflation would have created a background of gravitational waves that could have an observable effect. These waves would cause subtle, characteristic distortions of the cosmic microwave background (CMB)—the oldest light in the Universe, released when photons decoupled from matter and the Universe became transparent to radiation. Viewpoint: Peering Back to the Beginning of Time

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    First Direct Evidence of Cosmic Inflation


    Almost 14 billion years ago, the universe we inhabit burst into existence in an extraordinary event that initiated the Big Bang. In the first fleeting fraction of a second, the universe expanded exponentially, stretching far beyond the view of our best telescopes. All this, of course, was just theory.

     ***



     LSC Congratulates BICEP2 Colleagues

     

    18 March 2014 - The BICEP2 Collaboration result, if confirmed, is a landmark discovery in cosmology, allowing us for the first time to peer back almost to the moment of the Big Bang through the observation of the imprint of primordial gravitational waves on the cosmic microwave background. The LIGO Scientific Collaboration congratulates our BICEP colleagues on their accomplishment and will further follow discoveries and implications of these observations with great interest. - See more at: http://www.ligo.org/news/bicep-result.php#sthash.mJlemItG.dpuf
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    See Also:

    Thursday, April 10, 2014

    The Map of B Mode Imprints


    Figure 3: Left: BICEP2 apodized E-mode and B-mode maps filtered to 50 < ℓ < 120. Right: The equivalent maps for the first of the lensed-ΛCDM+noise simulations. The color scale displays the E-mode scalar and B-mode pseudoscalar patterns while the lines display the equivalent magnitude and orientation of the linear polarization. Note that excess B-mode is detected over lensing+noise with high signal-to-noise ratio in the map (s/n > 2 per map mode at ℓ ≈ 70). (Also note that the E-mode and B-mode maps use different color/length scales.)

    BICEP2 2014 Release Figures from Papers

     You know the distinctions on how one might see information as purported to exist as gravitational waves  of course held my perspective. Like others,  is this a way in which BICEP has illustrated something of the every nature of space-time, as to my thoughts then, when it really was only about seeing a footprint in the WMAP.


    Gravitational waves open up a new window on the universe that will allow us to probe events for which no electromagnetic signature exists. In the next few years, the ground-based interferometers GEO-600, LIGO, VIRGO and TAMA should be able to detect the high-frequency gravitational waves produced by extreme astrophysical objects, providing the first direct detection of these disturbances in space–time. With its much longer arm lengths, the space-based interferometer LISA will, if launched, be able to detect lower-frequency gravitational waves, possibly those generated by phase transitions in the early universe. At even lower frequencies, other experiments will look for tiny signatures of gravitational waves in the cosmic microwave background. Source: NASA.

    Gravity Wave Spectrum


    So it is a footprint then and I might show some of those maps and ask what do these footprints show in the early universe as to say, that given the inflationary timeline what can be garnered about looking back so far as to suggest 13.8 billion years and have such an imprint hold relevance, and equal the very nature of space-time itself.

    Figure 18: Results of far-field beam characterization with a chopped thermal source. Left: Typical measured far-field beam on a linear scale. Middle: The Gaussian fit to the measured beam pattern. Right: The fractional residual after subtracting the Gaussian fit. Note finer color scale in the right-hand differenced map.

    BICEP2 2014 Release Figures from Papers



    The nature of the question for me is a "sensor mode developmental model" that chooses to exemplify gravitational waves over another and I had to make this clear for myself. So you can see where this has lead me. To where I want to further understand. If you choose not to show a comment then I guess that is where I lose.

     
    Weber developed an experiment using a large suspended bar of aluminum, with a high resonant Q at a frequency of about 1 kH; the oscillation of the bar after it had been excited could be measured by a series of piezoelectric crystals mounted on it. The output of the system was put on a chart recorder like those used to record earthquakes. Weber studied the excursions of the pen to look for the occasional tone of a gravitational wave passing through the bar...

    See:Weber Bars Ring True?

    The analogy rests with how the nature of gravitational waves had been sounded so as to show a connection to the WMAP as a footprint. So you have this 2 dimensional map surface as to exemplary how gravitational waves may appear on it, yet,  the visual extent of that correlation is representative to me of a defined configuration space. You need your physics in order to establish any correlation to the timeline of the inflationary model and to see that such a map reveals efforts to penetrate the Planck era. To suggest quantum gravity.

    At least two detectors located at widely separated sites are essential for the unequivocal detection of gravitational waves. Local phenomena such as micro-earthquakes, acoustic noise, and laser fluctuations can cause a disturbance at one site, simulating a gravitational wave event, but such disturbances are unlikely to happen simultaneously at widely separated sites. 

    Correlating Gravitational Wave Production in LIGO
    See Also:


    So indeed to have such a map is very telling to me not just of the imprint but also of the sensory mode we had chosen to illustrate that map of the B mode representation as a valid model description of that early universe.

    Saturday, December 21, 2013

    Weber Bars Ring True?



    Gravitational Radiation

    Gravitational waves have a polarization pattern that causes objects to expand in one direction, while contracting in the perpendicular direction. That is, they have spin two. This is because gravity waves are fluctuations in the tensorial metric of space-time.


    How would you map this above?

    WMAP image of the Cosmic Microwave Background Radiation


    Here's the thing for those blog followers who are interested in the application of sound as a visual representation of an external world of senses.



     In this example I’m going to map speed to the pitch of the note, length/postion to the duration of the note and number of turns/legs/puffs to the loudness of the note.See: How to make sound out of anything.

    I have my reasons for looking at the trail that began with Gravitational wave research and development. If we are accustom to seeing and concreting all that reality has for us,  can a question be raised in mind with how one has been shocked by an anomaly?

    I am not asking for anyone  to abandon their views on the science of,  just respect that while not following the rules of  science here as to my motivational underpinnings, I have asked if science can see gravity in ways that have not be thought of before.  This is not to counter anything that has been done before.

    The historic approach to Gravitational Research was important as well,  to trace it back to it's beginning.

    Can we use such measures to exemplify an understanding of the world we live according  to a qualitative approach? This has occupied my thoughts back to when I first blogged about JosephWeber in 2005. Here is a 2000 article linked.
    In the late 1950s, Weber became intrigued by the relationship between gravitational theory and laboratory experiments. His book, General Relativity and Gravitational Radiation, was published in 1961, and his paper describing how to build a gravitational wave detector first appeared in 1969. Weber's first detector consisted of a freely suspended aluminium cylinder weighing a few tonnes. In the late 1960s and early 1970s, Weber announced that he had recorded simultaneous oscillations in detectors 1000 km apart, waves he believed originated from an astrophysical event. Many physicists were sceptical about the results, but these early experiments initiated research into gravitational waves that is still ongoing. Current gravitational wave experiments, such as the Laser Interferometer Gravitational Wave Observatory (LIGO) and Laser Interferometer Space Antenna (LISA), are descendants of Weber's original work. See:Joseph Weber 1919 - 2000
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    Space, we all know what it looks like. We've been surrounded by images of space our whole lives, from the speculative images of science fiction to the inspirational visions of artists to the increasingly beautiful pictures made possible by complex technologies. But whilst we have an overwhelmingly vivid visual understanding of space, we have no sense of what space sounds like.

      See previous entries on "Weber Bar" by typing in Search Feature on side bar. See also below.


    Thursday, August 29, 2013

    How to Find Black holes with Lasers



    In February 2013 I was invited by the Institute of Physics to give a lecture in the famous lecture theatre of the Royal Institution of Great Britain as part of their Physics in Perspective series. I was to expect about 400 students and teachers from schools across the country. See: How to Find Black holes with Lasers

     Freise_Finding_Black_Holes_with_Lasers_180213_reduced.pdf

    Saturday, May 04, 2013

    The LIGO and Virgo Gravitational-Wave Detectors

    An artist's impression of two stars orbiting each other (left). The orbit shrinks as the system emits gravitational waves (middle). When the stars merge (right), there is a resulting powerful emission of gravitational waves. [Image: NASA]

    The LIGO and Virgo gravitational-wave detectors have been hunting for signals from the collisions of neutron stars and black holes, which are dense objects formed from the remains of stars many times more massive than our Sun. When two of these objects orbit each other in a binary system, the emission of gravitational waves will gradually carry away some of their orbital energy, forcing them to get closer and closer together. This happens slowly at first, but as the orbit gets tighter the gravitational waves get stronger and the process accelerates until eventually the stars collide and merge, emitting in the last few seconds one of the most powerful outflows of energy in the Universe. See: What gravitational waves can tell us about colliding stars and black holes




    The LIGO Hanford Control Room
    LIGO's mission is to directly observe gravitational waves of cosmic origin. These waves were first predicted by Einstein's general theory of relativity in 1916, when the technology necessary for their detection did not yet exist. Gravitational waves were indirectly suggested to exist when observations were made of the binary pulsar PSR 1913+16, for which the Nobel Prize was awarded to Hulse and Taylor in 1993.
    The Binary Pulsar PSR 1913+16:




    See Also:



    Monday, November 26, 2012

    Observational Gravitational-Wave Astronomy.


    Figure 1: Gravitational wave strain and strain sensitivity for a 5 year observation with PTAs.
    The red dashed line is the approximate strain sensitivity for current PTAs (11), and the green
    dashed line shows the previous estimate for the stochastic signal strength that is currently in
    standard use for PTA analyses (13, 14). The dark blue solid line corresponds to our mean
    estimate for the stochastic signal strength, with the blue shaded region bound by thin solid
    blue lines showing our 95% confidence interval for this estimate, based on the observational
    uncertainties of our model parameters. The light blue (△ACD) and cyan (△ABE) shaded
    regions show the area corresponding to the square root of the 2 integrand, to be integrated over
    logarithmic frequency intervals as in Eq. (3), for our expected SNR of 8, and the SNR of 2
    expected from previous estimates (13, 14), respectively. See: The Imminent Detection Of Gravitational Waves From Massive Black-Hole Binaries With Pulsar Timing Arrays





    As mentioned in article by Technology Review the idea of previous information as to supplying data would have to be identified in future experiments as confirmations. In this instance information gained from Taylor and Hulse  in terms of binary star rotations closeness.

    Tuesday, July 17, 2012

    Brian Clegg: Gravity

    A history of gravity, and a study of its importance and relevance to our lives, as well as its influence on other areas of science. 
    Physicists will tell you that four forces control the universe. Of these, gravity may the most obvious, but it is also the most mysterious. Newton managed to predict the force of gravity but couldn’t explain how it worked at a distance. Einstein picked up on the simple premise that gravity and acceleration are interchangeable to devise his mind-bending general relativity, showing how matter warps space and time. Not only did this explain how gravity worked – and how apparently simple gravitation has four separate components – but it predicted everything from black holes to gravity’s effect on time. Whether it’s the reality of anti-gravity or the unexpected discovery that a ball and a laser beam drop at the same rate, gravity is the force that fascinates. Gravity: How the Weakest Force in the Universe Shaped Our Lives




    It is an interesting read so far. I have always had a fondness of the historical take information can  provide from that historical sense.  Each time an author can enlighten the world with our science forbears it makes for a deeper feel of what came out of these scientists as precursors to where we are today. I enjoy how Brian Clegg can fill in the gaps with what I had learn of Sir Isaac Newton. The historical progress from the ancient Greeks to what has transpire to today in terms of our definition of Gravity.

    It allows one to look at around them and the way in which early ideas became foundations points from which development move on toward the world of the science we have today in terms of that gravity.


    Tuesday, June 26, 2012

    Core Optics

    A pair of polished Advanced LIGO end mirrors (ETM's)
    Core optics are the 40-kg masses that form the heart of a LIGO detector. A core optic is manufactured from fused silica, polished to a few nanometers of smoothness and coated with dozens of layers of optical coatings. The result is a tuning of the balance of reflection and transmission of the mirror at the parts per million level. See: Advanced LIGO

    Wednesday, December 01, 2010

    Holometer

    Holometer Revised


    This plot shows the sensitivity of various experiments to fluctuations in space and time. Horizontal axis is the log of apparatus size (or duration time the speed of light), in meters; vertical axis is the log of the rms fluctuation amplitude in the same units. The lower left corner represents the Planck length or time. In these units, the size of the observable universe is about 26. Various physical systems and experiments are plotted. The "holographic noise" line represents the rms transverse holographic fluctuation amplitude on a given scale. The most sensitive experiments are Michelson interferometers.

    The Fermilab Holometer in Illinois is currently under construction and will be the world's most sensitive laser interferometer when complete, surpassing the sensitivity of the GEO600 and LIGO systems, and theoretically able to detect holographic fluctuations in spacetime.[1][2][3]

    The Holometer may be capable of meeting or exceeding the sensitivity required to detect the smallest units in the universe called Planck units.[1] Fermilab states, "Everyone is familiar these days with the blurry and pixelated images, or noisy sound transmission, associated with poor internet bandwidth. The Holometer seeks to detect the equivalent blurriness or noise in reality itself, associated with the ultimate frequency limit imposed by nature."[2]
    Craig Hogan, a particle astrophysicist at Fermilab, states about the experiment, "What we’re looking for is when the lasers lose step with each other. We’re trying to detect the smallest unit in the universe. This is really great fun, a sort of old-fashioned physics experiment where you don’t know what the result will be."

    Experimental physicist Hartmut Grote of the Max Planck Institute in Germany, states that although he is skeptical that the apparatus will successfully detect the holographic fluctuations, if the experiment is successful "it would be a very strong impact to one of the most open questions in fundamental physics. It would be the first proof that space-time, the fabric of the universe, is quantized."[1]

    References

    1. ^ a b c Mosher, David (2010-10-28). "World’s Most Precise Clocks Could Reveal Universe Is a Hologram". Wired. http://www.wired.com/wiredscience/2010/10/holometer-universe-resolution/. 
    2. ^ a b "The Fermilab Holometer". Fermi National Accelerator Laboratory. http://holometer.fnal.gov/. Retrieved 2010-11-01. 
    3. ^ Dillow, Clay (2010-10-21). "Fermilab is Building a 'Holometer' to Determine Once and For All Whether Reality Is Just an Illusion". Popular Science. http://www.popsci.com/science/article/2010-10/fermilab-building-holometer-determine-if-universe-just-hologram.

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    Fermilab Holometer
    About a hundred years ago, the German physicist Max Planck introduced the idea of a fundamental, natural length or time, derived from fundamental constants. We now call these the Planck length, lp = √hG/2π c3 = 1.6 × 10-35 meters. Light travels one Planck length in the Planck time, tp = √hG/2π c5 = 5.4 × 10-44seconds. 
    The physics of space and time is expected to change radically on such small scales. For example, a particle confined to a Planck volume automatically collapses to a black hole. 
    See: Fermilab Holometer

    ***

    A Conceptual Drawing of the 'Holometer' via Symmetry

    “The shaking of spacetime occurs at a million times per second, a thousand times what your ear can hear,” said Fermilab experimental physicist Aaron Chou, whose lab is developing prototypes for the holometer. “Matter doesn’t like to shake at that speed. You could listen to gravitational frequencies with headphones.”
    The whole trick, Chou says, is to prove that the vibrations don’t come from the instrument. Using technology similar to that in noise-cancelling headphones, sensors outside the instrument detect vibrations and shake the mirror at the same frequency to cancel them. Any remaining shakiness at high frequency, the researchers propose, will be evidence of blurriness in spacetime
    “With the holometer’s long arms, we’re magnifying spacetime’s uncertainty,” Chou said.
    See: Hogan’s holometer: Testing the hypothesis of a holographic universe

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    Conclusion:


    Wednesday, October 28, 2009

    Gravity is Talking, LISA will Listen

    It seems by measure the Interferometer has come a long way. If one recognizes how gravitational waves are measured, you come to understand how they can have a affect on laser light.

    Bee and Stefan of Backreaction have gone to visit the historical location of the beginnings of how we use interferometers.


    (click on Image for larger viewing)

    The Cosmos sings with many strong gravitational voices, causing ripples in the fabric of space and time that carry the message of tremendous astronomical events: the rapid dances of closely orbiting stellar remnants, the mergers of massive black holes millions of times heavier than the Sun, the aftermath of the Big Bang. These ripples are the gravitational waves predicted by Albert Einstein's 1915 general relativity; nearly one century later, it is now possible to detect them. Gravitational waves will give us an entirely new way to observe and understand the Universe, enhancing and complementing the insights of conventional astronomy.

    LISA, the Laser Interferometer Space Antenna, is a joint NASA–ESA mission to observe astrophysical and cosmological sources of gravitational waves of low frequencies (0.03 mHz to 0.1 Hz, corresponding to oscillation periods of about 10 hours to 10 seconds). This frequency band contains the emission from massive black-hole binaries that form after galactic mergers; the song of compact stellar remnants as they slowly spiral to their final fate in the black holes at the centers of galaxies; the chorus of millions of compact binariesshortly after the Big Bang.

    LISA consists of three identical spacecraft flying in a triangular constellation, with equal arms of 5 million kilometers each. As gravitational waves from distant sources reach LISA, they warp space-time, stretching and compressing the triangle. Thus, by precisely monitoring the separation between the spacecraft, we can measure the waves; and by studying the shape and timing of the waves we can learn about the nature and evolution of the systems that emitted them.

    Tuesday, September 22, 2009

    Correlating Gravitational Wave Production in LIGO



    Drawing by Glen Edwards, Utah State University, Logan, UT

    The most important thing is to be motivated by your own intellectual curiosity.KIP THORNE



    ***





    Fig. 1. The four forces (or interactions) of Nature, their force carrying particles and the phenomena or particles affected by them. The three interactions that govern the microcosmos are all much stronger than gravity and have been unified through the Standard Model

    ***




    Dr. Kip Thorne, Caltech 01-Relativity-The First 20th Century Revolution

    ***

    Why are two installations necessary?





    ***



    See: LIGO Listens for Gravitational Echoes of the Birth of the Universe

    Results set new limits on gravitational waves originating from the Big Bang; constrain theories about universe formation

    Pasadena, Calif.—An investigation by the LIGO (Laser Interferometer Gravitational-Wave Observatory) Scientific Collaboration and the Virgo Collaboration has significantly advanced our understanding of the early evolution of the universe.

    Analysis of data taken over a two-year period, from 2005 to 2007, has set the most stringent limits yet on the amount of gravitational waves that could have come from the Big Bang in the gravitational wave frequency band where LIGO can observe. In doing so, the gravitational-wave scientists have put new constraints on the details of how the universe looked in its earliest moments.

    Much like it produced the cosmic microwave background, the Big Bang is believed to have created a flood of gravitational waves—ripples in the fabric of space and time—that still fill the universe and carry information about the universe as it was immediately after the Big Bang. These waves would be observed as the "stochastic background," analogous to a superposition of many waves of different sizes and directions on the surface of a pond. The amplitude of this background is directly related to the parameters that govern the behavior of the universe during the first minute after the Big Bang.

    Earlier measurements of the cosmic microwave background have placed the most stringent upper limits of the stochastic gravitational wave background at very large distance scales and low frequencies. The new measurements by LIGO directly probe the gravitational wave background in the first minute of its existence, at time scales much shorter than accessible by the cosmic microwave background.
    The research, which appears in the August 20 issue of the journal Nature, also constrains models of cosmic strings, objects that are proposed to have been left over from the beginning of the universe and subsequently stretched to enormous lengths by the universe's expansion; the strings, some cosmologists say, can form loops that produce gravitational waves as they oscillate, decay, and eventually disappear.

    Gravitational waves carry with them information about their violent origins and about the nature of gravity that cannot be obtained by conventional astronomical tools. The existence of the waves was predicted by Albert Einstein in 1916 in his general theory of relativity. The LIGO and GEO instruments have been actively searching for the waves since 2002; the Virgo interferometer joined the search in 2007.

    The authors of the new paper report that the stochastic background of gravitational waves has not yet been discovered. But the nondiscovery of the background described in the Nature paper already offers its own brand of insight into the universe's earliest history.

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