Judith Kerr Albert Einstein Judith KerrDalai LamaAlbert Einstein.
Beyond Einstein
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Transcript of Beyond Einstein
7/15/2019 Beyond Einstein
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WHAT POWERED
THE BIG BANG?
WHAT HAPPENS
AT THE EDGE
OF A BLACK HOLE?
WHAT IS
DARK ENERGY?
National Aeronautics andSpace Administration
Presented b y Dr. James Lochner (USRA & NASA /GSFC)
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BEYOND EINSTEIN
Beyond Einstein
• Einstein’s Predictions
• Expanding Universe
• Black Holes
• Dark Energy
• Evidence for those predictions
•
Lingering Questions … • What Powered the Big Bang?
• What Happens at the Edge of a Black Hole?
• What is Dark Energy?
• … And How We’ll Answer them
• LISA
• Constellation-X
• Implications for Your Students
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BEYOND EINSTEIN
Einstein changed the way we think of the universe:
•
The speed of light is the ultimate speed limit.• Time passes more slowly for observers traveling at high
speeds or near a massive body.
• Light rays can be bent passing near a massive body.
Einstein & Our Universe
These predictions have been confirmed by observations.
Einstein’s theories also made three startling predictions:
• The expansion of the Universe (from a big bang)
• Black Holes
•
Cosmological Constant(acting against pull of gravity)
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BEYOND EINSTEIN
Evidence for the Expanding Universe
• We know about Expanding Universe &
Big Bang from:
• Hubble’s discovery of red-shifted
galaxies.
• Penzias & Wilson discovery of 3 K
background.
• Abundances of the light elements.
•
Big Bang alone doesn’t quite producethe universe we see.
• Inflation produces a flat universe.
• A growth spurt that stretches sub-atomic scales to
astronomical scales.
• Produces the fluctuations that lead to galaxies.
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BEYOND EINSTEIN
Evidence for Black Holes
• Black holes in 3 flavors
• Stellar (5 - 15 solar masses)
o Evident in X-ray Binary Systems
• Massive (Million solar masses)
o In center of galaxies
• Intermediate (Thousand solar masses)
o Within galaxies, but not in center
• Abundant Observations and Evidence
• We measure masses (e.g from binary systems).
• We observe radiation from gaseous disks surrounding the
black hole.
• We see effects of strong gravity on nearby matter.
o First evidence for frame dragging and black hole rotation.
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BEYOND EINSTEIN
Evidence for Dark Energy
Dark Energy revealed itself in a survey of
supernovae in the late 1990’s.
We can use certain types of supernovae to
determine distances to galaxies.
We then compare those distances with the
galaxy’s velocity.
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BEYOND EINSTEIN
A dying star becomes a white dwarf.
1. Create a White Dwarf
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BEYOND EINSTEIN
The white dwarf strips gas from its stellar companion….
2. Dump more mass onto it
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BEYOND EINSTEIN
….and uses it to become a hydrogen bomb. Bang!
3. Until it explodes
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BEYOND EINSTEIN
The explosion is as bright as an entire galaxy of stars….
…..and can be seen in galaxies across the universe.
4. Observe it in a distant galaxy
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BEYOND EINSTEIN
Evidence for Dark Energy
SN Ia are more distant than expected.
Spacetime has expanded more than
expected.
R e d s h i f t
Distance via SN Ia
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BEYOND EINSTEIN
We do not know what 95% of the universe is made of!
Dark Energy and the Universe
Flatness of Universe and amount of known
matter (and dark matter) means dark energy
makes up 70% of the Universe
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BEYOND EINSTEIN
Completing Einstein’s Legacy
BIG BANG
What powered the Big Bang?
BLACK HOLESWhat happens at the edge of a Black Hole?
DARK ENERGY
What is the mysterious Dark Energy pullingthe Universe apart?
Einstein’s legacy is incomplete, his theory fails to explain the
underlying physics of the very phenomena his work predicted
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BEYOND EINSTEIN
What Powered the Big Bang?
Inflation
(Big Bang plus
10-34 Seconds)
Big Bang plus300,000 Years
Big Bang plus
14 Billion Years
What Powered the Big Bang?Gravitational Waves Can Escape from
Earliest Moments of the Big Bang
Nowgravitational waves
light
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BEYOND EINSTEIN
Gravitational waves coming from
Inflation period and from “phase transitions”
may be detected directly.
• Free quarks becoming bound into protons, neutrons, etc
• Decoupling of the Electroweak and Strong forces
Wavelength of the Gravitational Waves gives size of
Universe at that time.
What Powered the Big Bang?
BEYOND EINSTEIN
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BEYOND EINSTEIN
Sources of Gravitational Waves
QuickTime™ an d a
Photo decompressor are needed to see this picture.
•
Black holes orbiting each other generate gravitationalwaves.
• Merging black holes also generate gravitational
waves.
BEYOND EINSTEIN
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BEYOND EINSTEIN
Catching a Gravitational Wave
BEYOND EINSTEIN
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BEYOND EINSTEIN
Laser Interferometer Space Antenna (LISA)
LISA uses a laser based Michelson
interferometer to monitor the
separation between proof masses in
separate spacecraft.
Joint ESA-NASA project
• Three spacecraft separated by 5 million km.
• Each spacecraft includes two freely falling test masses.
• Distance changes measured with precision of 4 ppm
RMS over 100 seconds.
BEYOND EINSTEIN
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BEYOND EINSTEIN
Close to a black hole event horizon,
extreme distortions of space & time
predicted by Einstein can be observed
Black holes are ubiquitous in the Universe
Chandra Deep Image
What Happens at the Edge of a Black
Hole?
BEYOND EINSTEIN
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BEYOND EINSTEIN
What Happens at the Edge of a Black
Hole?
• Japan-US ASCA satellite studied iron gas orbiting near the event horizon of a black hole.
• Iron line emission exhibits a distortion due to motion of
gas and strong gravitational effects near the black
hole.
• Line profile provides a probe of regions near blackhole.
QuickTime™ an d a
YUV420 codec decompressor are needed to see this p icture.
BEYOND EINSTEIN
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BEYOND EINSTEIN
Measuring Black Holes via Spectroscopy
• Better determination of black hole parameters by
studying individual blobs falling into event horizon.
• Measure effects of black hole spin on nearby space-
time.
• Study intermediate size black holes.
• Growth of supermassive black holes early in the
universe.
BEYOND EINSTEIN
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BEYOND EINSTEIN
Constellation-X
A fleet of 4 X-ray Telescopes to perform highresolution spectroscopy on faint x-ray sources
• Each telescope 10 meter focal length.
• 4 telescopes increase the light collection area.
• Launched on two Delta rockets.
• Placed at L2 point (4x distance to moon)
• 4 - 10 year lifetime.
BEYOND EINSTEIN
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BEYOND EINSTEIN
Constellation-X: Achieving High
Resolution Spectroscopy
X-ray Microcalorimeter Spectrometer:Measure the heat from an x-ray to determine the
x-ray’s energy.
Resolution of 4 ev for a 6 kev x-rayenergy. (25x-100x better than current
sensitivity.)
QuickTime™ an d aGIF decompressor
are needed to see this picture.
BEYOND EINSTEIN
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BEYOND EINSTEIN
What is the Dark Energy?
Einstein introduced the Cosmological Constant to explain what was
then thought to be a static Universe, “my biggest mistake . . . ”
Empty space has energy. It’s
gravitational effect pushes the
universe apart.
Need a form of energy that is elastic:
• Vacuum energy (= Cosmol. Const.)
• But it’s effect may be too large
• Quintessence (particle field)
Astronomical Tools: Surveillance & Interrogation
• Measure expansion via fluctuations in CMB.
• Measure expansion via more SN and clusters of
galaxies.
BEYOND EINSTEIN
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BEYOND EINSTEIN
Constellation-X and Dark Energy
• Dark Energy with Galaxy Clusters- Compare Distance with redshift to measure history of
expansion of the universe.
- Examine the growth of structure in the universe.
BEYOND EINSTEIN
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BEYOND EINSTEIN
Realizing Science Beyond Einstein
1. Einstein Great Observatories providing breakthroughincreases in capabilities to address all BeyondEinstein science:
• LISA: Gravitational waves from merging black holes and theearly Universe.
•
Constellation-X: Spectroscopy close to the event horizon of black holes and place constraints on dark side of the Universe.
2. Einstein Probes to address focused scienceobjectives:
• Determine the amount and nature of the Dark Energy.
• Search for the signature of inflation in the microwavebackground via gravitational waves.
• Take a census of Black Holes of all sizes in the Universe.
3. A technology program, theoretical studies and aneducation program to inspire future generations of scientists and engineers towards the vision:
• Directly detect the gravitational waves emitted during theBig Bang.
• Image and resolve the event horizon of a Black Hole.
Three inter-linked components that work together:
BEYOND EINSTEIN
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BEYOND EINSTEIN
Image a Black Hole!
0.1 arc sec resolutionHST Image M87
Black Hole Imager 0.1 micro arc sec resolution
4-8 m arc sec
Hubble, Chandra, and other observatories
are showing black holes are common place
in the Universe.
Black holes provide a unique laboratory
to test Einstein’s theory of gravity.
A future black hole imager with a resolution
one million times Hubble will observe the
effects Einstein predicted.
X-ray emission from close to the eventhorizon provides a powerful probe.
BEYOND EINSTEIN
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BEYOND EINSTEIN
Observe the Big Bang
• Detect the gravitational waves from the earliest
moments after the Big Bang.• Provides a direct view of the formation of space
and time.
• Big Bang Observer will also detect mergers of
neutron stars and black holes, giving the rate of expansion of the universe through time.
BEYOND EINSTEIN
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BEYOND EINSTEIN
Beyond Einstein Timeline
BEYOND EINSTEIN
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BEYOND EINSTEIN
The Story of “Beyond Einstein”
• Science is an endless frontier
• Einstein changed our way of thinking about the universe,but we are going beyond that.
• Science is a search for answers
• Nature of science inquiry
• Science as a process and as a human endeavor.
• When we do not know the answers, we work on
phrasing the questions.
• We push the envelope of what we know.
• We push the envelope of our technology.
BEYOND EINSTEIN
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BEYOND EINSTEIN
How did the Universebegin? Does time
have beginning & an
end? Does space
have edges? The
questions are as oldas human curiosity.
But the answers have
always seemed
beyond the reach of
science. . .until now!
The 21st Century
BEYOND EINSTEIN
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Dark Energy Probe
• Determine amount of dark energy, and whether it changes.
• Ex. Search for large numbers of Type Ia supernovae.
Inflation Probe
• Map polarization of Microwave Background to search for signature of gravitational waves from the Big Bang.
Black Hole Finder Probe
• Take census of black holes in the universe
• Ex. Use wide-field X-ray telescope
Einstein Probes
Three focused missions, each designed to address a
single high priority science question: