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終於要發現螺旋之力了啊！

https://www.youtube.com/watch?v=Cz7RI4MTQqM

https://goo.gl/sMols4

Keck Observatory Sheds Light on ‘Fifth Force’
By W. M. Keck Observatory on Maunakea
Posted May 31, 2017, 10:22 AM HST

The orbits of two stars, S0-2 and S0-38, located near the Milky Way’s
supermassive black hole, will be used to test Einstein’s Theory of General
Relativity and potentially generate new gravitational models. IMAGE CREDIT:
S. SAKAI/A.GHEZ/W. M. KECK OBSERVATORY/ UCLA GALACTIC CENTER GROUP.
W. M. Keck Observatory data has led to a first-of-its-kind test of Einstein’
s Theory of General Relativity.

A UCLA-led team has discovered a new way of probing the hypothetical fifth
force of nature using two decades of observations at Maunakea’s W. M. Keck
Observatory, the world’s most scientifically productive ground-based
telescope.

There are four known forces in the universe: electromagnetic force, strong
nuclear force, weak nuclear force and gravitational force. Physicists know
how to make the first three work together, but gravity is the odd one out.
For decades, there have been theories that a fifth force ties gravity to the
others, but no one has been able to prove it thus far.


UCLA Professor of Astrophysics and Galactic Center Group Director Andrea
Ghez, a Keck Observatory astronomer and recipient of the 2015 Bakerian Medal.
IMAGE CREDIT: KYLE ALEXANDER.
“This is really exciting,” said Andrea Ghez, director of the UCLA Galactic
Center Group and co-author of the study. “It’s taken us 20 years to get
here, but now our work on studying stars at the center of our galaxy is
opening up a new method of looking at how gravity works.”

The research is published in the current issue of Physical Review Letters.

Ghez and her co-workers analyzed extremely sharp images of the center of our
galaxy taken with Keck Observatory’s adaptive optics (AO). Ghez used this
cutting-edge system to track the orbits of stars near the supermassive black
hole located at the center of the Milky Way. Their stellar path, driven by
gravity created from the supermassive black hole, could give clues to the
fifth force.

“By watching the stars move over 20 years using very precise measurements
taken from Keck Observatory data, you can see and put constraints on how
gravity works,” said Ghez. “If gravitation is driven by something other
than Einstein’s theory of General Relativity, you’ll see small variations
in the orbital paths of the stars.”

This is the first time the fifth force theory has been tested in a strong
gravitational field such as the one created by the supermassive black hole at
the center of the Milky Way. Historically, measurements of our solar system’
s gravity created by our sun have been used to try and detect the fifth
force, but that has proven difficult because its gravitational field is
relatively weak.

“It’s exciting that we can do this because we can ask a very fundamental
question—how does gravity work?” said Ghez. “Einstein’s theory describes
it beautifully well, but there’s lots of evidence showing the theory has
holes. The mere existence of supermassive black holes tells us that our
current theories of how the universe works are inadequate to explain what a
black hole is.”

Ghez and her team, including lead author Aurelien Hees and co-author Tuan Do,
both of UCLA, are looking forward to summer of 2018. That is when the star
S0-2 will be at its closest distance to our galaxy’s supermassive black
hole. This will allow the team to witness the star being pulled at maximum
gravitational strength—a point where any deviations to Einstein’s theory is
expected to be the greatest.

About Adaptive Optics
W. M. Keck Observatory is a distinguished leader in the field of adaptive
optics (AO), a breakthrough technology that removes the distortions caused by
the turbulence in the Earth’s atmosphere. Keck Observatory pioneered the
astronomical use of both natural guide star (NGS) and laser guide star
adaptive optics (LGS AO) and our current systems now deliver images three to
four times sharper than the Hubble Space Telescope. AO has imaged the four
massive planets orbiting the star HR8799, measured the mass of the giant
black hole at the center of our Milky Way Galaxy, discovered new supernovae
in distant galaxies, and identified the specific stars that were their
progenitors.

About W. M. Keck Observatory
The W. M. Keck Observatory operates the largest, most scientifically
productive telescopes on Earth. The two, 10-meter optical/infrared telescopes
on the summit of Maunakea on the Island of Hawaii feature a suite of advanced
instruments including imagers, multi-object spectrographs, high-resolution
spectrographs, integral-field spectrometers, and world-leading laser guide
star adaptive optics systems. The Observatory is a private 501(c) 3
non-profit organization and a scientific partnership of the California
Institute of Technology, the University of California, and NASA.

大意↓









Ghez教授說，如果引力是由愛因斯坦廣義相對論以外的東西驅動的，那麼恆星的軌道將會
出現微小變化。



https://www.youtube.com/watch?v=yRavrj4r1Xw


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你知道嗎?人體由75兆獨立細胞組成.在我們死之前,他們通常不會一直伴隨我們﹍有一些能
存活幾天,而另一些能存活幾年.我們不會受它們的壽命影響,它們會被新的細胞所代替,這
能幫助我們維持自身.我覺得沒人會爭論我們會因為這個進程而丟失形象,很明顯,我們在不
斷地轉變.那麼,我們是如何保持原樣的?連續不斷的思維和感知造成一些序列連續性,也就
是我們自己.我們的意識不是我們大腦的一部分,而是不斷湧現的實體.讓你的身體死去,繼
續活在數據天堂的群星裡.    https://youtu.be/K5CECc7zXQ4?t=16m20s    《SOMA》

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