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PHVSICS OF THE IMPOSSIBLE
Big Splat theory, for example, differs from the radiation predicted by
some of the inflation theories, so LISA might be able to rule out several
of these theories. Obviously, these pre-big bang models cannot be
tested directly, since they involve understanding the universe before
the creation of time itself, but we can test them indirectly since each of
these theories predicts a different radiation spectrum emerging afterward from the big bang.
Physicist Rip Thorne writes, "Sometime between 2008 and 2030,
gravitational waves from the Big Bang singularity will be discovered.
There will ensue an era, lasting at least until 2050 ... These efforts will
reveal intimate details of the Big Bang singularity, and will thereby
verify that some version of string theory is the correct quantum theory
of gravity."
If LISA is unable to differentiate between different pre-big bang
theories, its successor, the Big Bang Observer (BBO) might. It is tentatively scheduled for launch in 2025. The BBO will be able to scan the
entire universe for all binary systems involving neutron stars and
black holes with mass less than one thousand times the mass of the
sun. But its main goal is to analyze gravity waves emitted during the
inflationary phase of the big bang. In this sense, the BBO is specifically
designed to probe the predictions of the inflationary big bang theory.
The BBO is somewhat similar to LISA in design. It will consist of
three satellites moving together in an orbit around the sun, separated
from each other by 50,000 kilometers (these satellites will be much
closer to one another than LISA'S satellites). Each satellite will be able
to fire a 300-watt laser beam. BBO will be able to probe gravity wave
frequencies between LIGO and LISA, filling an important gap. (LISA
can detect gravity waves from 10 to 3,000 hertz, while LIGO can detect
gravity waves of frequency 10 microhertz to 10 millihertz. BBO will be
able to detect frequencies that include both ranges.)
"By 2040 we will have used those laws [of quantum gravity] to produce high-confidence answers to many deep and puzzling questions,"
Thorne writes, "including ... What came before the Big Bang singularity, or was there even such a thing as a 'before'? Are there other universes? And if so, how are they related to or connected to our own
PHVSICS OF THE IMPOSSIBLE
Big Splat theory, for example, differs from the radiation predicted by
some of the inflation theories, so LISA might be able to rule out several
of these theories. Obviously, these pre-big bang models cannot be
tested directly, since they involve understanding the universe before
the creation of time itself, but we can test them indirectly since each of
these theories predicts a different radiation spectrum emerging afterward from the big bang.
Physicist Rip Thorne writes, "Sometime between 2008 and 2030,
gravitational waves from the Big Bang singularity will be discovered.
There will ensue an era, lasting at least until 2050 ... These efforts will
reveal intimate details of the Big Bang singularity, and will thereby
verify that some version of string theory is the correct quantum theory
of gravity."
If LISA is unable to differentiate between different pre-big bang
theories, its successor, the Big Bang Observer (BBO) might. It is tentatively scheduled for launch in 2025. The BBO will be able to scan the
entire universe for all binary systems involving neutron stars and
black holes with mass less than one thousand times the mass of the
sun. But its main goal is to analyze gravity waves emitted during the
inflationary phase of the big bang. In this sense, the BBO is specifically
designed to probe the predictions of the inflationary big bang theory.
The BBO is somewhat similar to LISA in design. It will consist of
three satellites moving together in an orbit around the sun, separated
from each other by 50,000 kilometers (these satellites will be much
closer to one another than LISA'S satellites). Each satellite will be able
to fire a 300-watt laser beam. BBO will be able to probe gravity wave
frequencies between LIGO and LISA, filling an important gap. (LISA
can detect gravity waves from 10 to 3,000 hertz, while LIGO can detect
gravity waves of frequency 10 microhertz to 10 millihertz. BBO will be
able to detect frequencies that include both ranges.)
"By 2040 we will have used those laws [of quantum gravity] to produce high-confidence answers to many deep and puzzling questions,"
Thorne writes, "including ... What came before the Big Bang singularity, or was there even such a thing as a 'before'? Are there other universes? And if so, how are they related to or connected to our own