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.

***
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:

Saturday, February 20, 2016

Sunyaev–Zel'dovich effect

The Sunyaev–Zel'dovich effect (often abbreviated as the SZ effect) is the result of high energy electrons distorting the cosmic microwave background radiation (CMB) through inverse Compton scattering, in which the low energy CMB photons receive an average energy boost during collision with the high energy cluster electrons. Observed distortions of the cosmic microwave background spectrum are used to detect the density perturbations of the universe. Using the Sunyaev–Zel'dovich effect, dense clusters of galaxies have been observed.

Contents

Introduction


The Sunyaev–Zel'dovich effect can be divided into:
  • thermal effects, where the CMB photons interact with electrons that have high energies due to their temperature
  • kinematic effects, a second-order effect where the CMB photons interact with electrons that have high energies due to their bulk motion (also called the Ostriker–Vishniac effect, after Jeremiah P. Ostriker and Ethan Vishniac.[1])
  • polarization
Rashid Sunyaev and Yakov Zel'dovich predicted the effect, and conducted research in 1969, 1972, and 1980. The Sunyaev–Zel'dovich effect is of major astrophysical and cosmological interest. It can help determine the value of the Hubble constant. To distinguish the SZ effect due to galaxy clusters from ordinary density perturbations, both the spectral dependence and the spatial dependence of fluctuations in the cosmic microwave background are used. Analysis of CMB data at higher angular resolution (high l values) requires taking into account the Sunyaev–Zel'dovich effect.

First detected by Mark Birkinshaw at the University of Bristol

Current research is focused on modelling how the effect is generated by the intracluster plasma in galaxy clusters, and on using the effect to estimate the Hubble constant and to separate different components in the angular average statistics of fluctuations in the background. Hydrodynamic structure formation simulations are being studied to gain data on thermal and kinetic effects in the theory.[2] Observations are difficult due to the small amplitude of the effect and to confusion with experimental error and other sources of CMB temperature fluctuations. However, since the Sunyaev–Zel'dovich effect is a scattering effect, its magnitude is independent of redshift. This is very important: it means that clusters at high redshift can be detected just as easily as those at low redshift. Another factor which facilitates high-redshift cluster detection is the angular scale versus redshift relation: it changes little between redshifts of 0.3 and 2, meaning that clusters between these redshifts have similar sizes on the sky. The use of surveys of clusters detected by their Sunyaev–Zel'dovich effect for the determination of cosmological parameters has been demonstrated by Barbosa et al. (1996). This might help in understanding the dynamics of dark energy in forthcoming surveys (SPT, ACT, Planck).

 

Timeline of observations

 

See also

 

References


  • Ostriker, Jeremiah P. & Vishniac, Ethan T. (1986). "Effect of gravitational lenses on the microwave background, and 1146+111B,C". Nature 322 (6082): 804. Bibcode:1986Natur.322..804O. doi:10.1038/322804a0.
  • Cunnama D., Faltenbacher F.; Passmoor S., Cress C.; Cress, C.; Passmoor, S. (2009). "The velocity-shape alignment of clusters and the kinetic Sunyaev-Zeldovich effect". MNRAS Letters 397 (1): L41–L45. arXiv:0904.4765. Bibcode:2009MNRAS.397L..41C. doi:10.1111/j.1745-3933.2009.00680.x.
  • Hand, Nick; Addison, Graeme E.; Aubourg, Eric; Battaglia, Nick; Battistelli, Elia S.; Bizyaev, Dmitry; Bond, J. Richard; Brewington, Howard; Brinkmann, Jon; Brown, Benjamin R.; Das, Sudeep; Dawson, Kyle S.; Devlin, Mark J.; Dunkley, Joanna; Dunner, Rolando; Eisenstein, Daniel J.; Fowler, Joseph W.; Gralla, Megan B.; Hajian, Amir; Halpern, Mark; Hilton, Matt; Hincks, Adam D.; Hlozek, Renée; Hughes, John P.; Infante, Leopoldo; Irwin, Kent D.; Kosowsky, Arthur; Lin, Yen-Ting; Malanushenko, Elena; et al. (2012). "Detection of Galaxy Cluster Motions with the Kinematic Sunyaev-Zel'dovich Effect". Physical Review Letters 109 (4): 041101. arXiv:1203.4219. Bibcode:2012PhRvL.109d1101H. doi:10.1103/PhysRevLett.109.041101. PMID 23006072.
  • Mroczkowski, Tony; Dicker, Simon; Sayers, Jack; Reese, Erik D.; Mason, Brian; Czakon, Nicole; Romero, Charles; Young, Alexander; Devlin, Mark; Golwala, Sunil; Korngut, Phillip; Sarazin, Craig; Bock, James; Koch, Patrick M.; Lin, Kai-Yang; Molnar, Sandor M.; Pierpaoli, Elena; Umetsu, Keiichi; Zemcov, Michael (2012). "A Multi-wavelength Study of the Sunyaev-Zel'dovich Effect in the Triple-merger Cluster MACS J0717.5+3745 with MUSTANG and Bolocam". Astrophysical Journal 761: 47. arXiv:1205.0052. Bibcode:2012ApJ...761...47M. doi:10.1088/0004-637X/761/1/47 (inactive 2015-01-09).

  • Sayers, Jack; Mroczkowski, T.; Zemcov, M.; Korngut, P. M.; Bock, J.; Bulbul, E.; Czakon, N. G.; Egami, E.; Golwala, S. R.; Koch, P. M.; Lin, K.-Y.; Mantz, A.; Molnar, S. M.; Moustakas, L.; Pierpaoli, E.; Rawle, T. D.; Reese, E. D.; Rex, M.; Shitanishi, J. A.; Siegel, S.; Umetsu, K. (2013). "A Measurement of the Kinetic Sunyaev-Zel'dovich Signal Toward MACS J0717.5+3745". Astrophysical Journal 778: 52. arXiv:1312.3680. Bibcode:2013ApJ...778...52S. doi:10.1088/0004-637X/778/1/52.

  • Further reading

    External links

    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.

    ***

    See:

    Saturday, February 06, 2016

    Homodyne detection


    Optical Homodyne Detection.

    Homodyne detection is a method of detecting frequency-modulated radiation by non-linear mixing with radiation of a reference frequency, the same principle as for heterodyne detection.

    In optical interferometry, homodyne signifies that the reference radiation (i.e. the local oscillator) is derived from the same source as the signal before the modulating process. For example, in a laser scattering measurement, the laser beam is split into two parts. One is the local oscillator and the other is sent to the system to be probed. The scattered light is then mixed with the local oscillator on the detector. This arrangement has the advantage of being insensitive to fluctuations in the frequency of the laser. Usually the scattered beam will be weak, in which case the (nearly) steady component of the detector output is a good measure of the instantaneous local oscillator intensity and therefore can be used to compensate for any fluctuations in the intensity of the laser.

    Homodyne and heterodyne techniques are commonly used in thermoreflectance techniques.

    Homodyne detection was one of the key techniques in demonstrating spooky action at a distance.[1]

    Contents

    Radio technology

    In radio technology, the distinction is not the source of the local oscillator, but the frequency used. In heterodyne detection, the local oscillator is frequency-shifted, while in homodyne detection it has the same frequency as the radiation to be detected. See direct conversion receiver.

    See also

    References

    1. Maria Fuwa, Shuntaro Takeda, Marcin Zwierz, Howard M. Wiseman & Akira Furusawa (24 March 2015). "Experimental proof of nonlocal wavefunction collapse for a single particle using homodyne measurements". Nature Communications 6 (6665): 6665. doi:10.1038/ncomms7665.

    When Black Holes Collide



    See also: What Happens When Black Holes Collide? - Kip Thorne

     

    Inside Einstein's Mind



    See Also: Inside Einstein's Mind | NOVA - PBS Documentary 

    Friday, February 05, 2016

    Heaven, is a State of Mind

    The idea about heaven in the regard with which you ponder, is it not very far away then? Meaning, that heaven is really right next door to you all the time. Heaven then, could be a state of mind, consciousness where we can move in time in very interesting ways. Heaven literally then, could sit in the very same space that you are standing in? So this idea then rests on how one may interpret geometric dimensional attributes as facets and degrees with which we access not only the future, but about how that future affects the past.

     I see a clock, but I cannot envision the clockmaker. The human mind is unable to conceive of the four dimensions, so how can it conceive of a God, before whom a thousand years and a thousand dimensions are as one?
    • From Cosmic religion: with other opinions and aphorisms (1931), Albert Einstein, pub. Covici-Friede. Quoted in The Expanded Quotable Einstein, Princeton University Press; 2nd edition (May 30, 2000); Page 208, ISBN 0691070210

    While in the film we see physical manifestations as gravitational waves,  as a bar code and a distribution of dust according to those patterns, these are derivatives of some higher dimensional thinking being communicated from the Tesseract, as books falling to the floor. So the gravitational waves have "a source" from which information is attained. The watch,  as time being communicated in the second hand. We use time as a means of representing a fourth physical dimension.

    Penrose's Influence on Escher
    During the later half of the 1950’s, Maurits Cornelius Escher received a letter from Lionel and Roger Penrose. This letter consisted of a report by the father and son team that focused on impossible figures. By this time, Escher had begun exploring impossible worlds. He had recently produced the lithograph Belvedere based on the “rib-cube,” an impossible cuboid named by Escher (Teuber 161). However, the letter by the Penroses, which would later appear in the British Journal of Psychology, enlightened Escher to two new impossible objects; the Penrose triangle and the Penrose stairs. With these figures, Escher went on to create further impossible worlds that break the laws of three-dimensional space, mystify one’s mind, and give a window to the artist heart.

    I think artists in some way explore these limitations of how such a thought construct could have been realized and in regards to Dali (are such dimensional attributes really inaccessible to the mind?), while we may make comments on his character, this does not limit one to realize how the Tesseractbecomes the measure that heaven can be seen in the construct of such thoughts you are engaged in.

    The implied idea of symmetry(the God Particle),  possibly, as to perfection in the way one may look at heaven and in Plato's case regardless of how old the philosophy is, it helps to point to some ideas about how the Catholic religion in Rome grabbed hold of Plato by a finger, as pointing up in relation to Aristotle in the School of Athen's fresco done by Raphael in the Signatore's rooms at the Vatican.