For nearly a century, scientists have
known and hypothesized about the
concept of absolute zero, the lowest
possible temperature (approximately -
5 459.4 degrees Fahrenheit).
Theoretically, at absolute zero matter
comes to a complete standstill, since
any motion would generate heat and
raise the temperature. However,
10 scientists are still uncertain about
exactly what happens to matter when it
reaches absolute zero. Does it simply
maintain its form, as if in a state of
suspended animation, or does it break
15 down into subatomic particles?
Scientists have some ideas about how
such matter might behave from studies
of both superconductivity (a state in
which atomic particles behave in an
20 unusually orderly manner, allowing
electrical current to flow with no
resistance) and superfluidity (another
abnormally orderly atomic state that
allows liquids to pass through solids). In
25 both states, particles and atoms move
practically in lockstep, allowing
phenomena that are usually prevented
by the randomness of atomic motion.
But few would venture to guess whether
30 matter continues along the same orderly
scale, or whether at absolute zero it
makes a quantum leap to a new state.
Recent breakthroughs have allowed
scientists to create near-absolute-zero
35 conditions in the laboratory. After
studying the new data, most physicists
now agree that, at absolute zero, atoms
will condense into a single entity, in
effect becoming one large atom. This
40 transition is known as Bose-Einstein
condensation. The question still
remains: will a Bose-Einstein
condensate behave in a super-orderly
manner in other hyper-cold states?
45 Some scientists theorize that its state
will be extremely unstable, while others
maintain that matter in absolute zero will
be tremendously stable because it will
be free from motion. Scientists have
50 created atmospheres as cold as one
microkelvin (one-millionth of a degree
above absolute zero), but have not
reached absolute zero itself: the task is
daunting, because the colder atoms get,
55 the more prone they are to soaking up
energy from any surrounding source,
thereby raising their temperatures.
Some pessimists in the field suspect
that it will be centuries before any group
60 of atoms can be chilled to a state of
absolute zero.
Q)Which of the following can be inferred from the passage about the relationship between the temperatures of absolute zero and one degree microkelvin?
(A)The formation of a Bose-Einstein condensate occurs at both temperatures, although the condensate is more stable at the temperature of absolute zero.
(B) For all practical purposes, the two are indistinguishable, since it would take many centuries for a group of atoms to cool to absolute zero.
(C)While scientists theorize that matter behaves differently at these two temperatures, no experimental evidence of these different behaviors as yet exists.
(D)At one degree microkelvin, matter is in a state of superconductivity, whereas at absolute zero it is not.
(E)Matter always assumes the form of a Bose-Einstein condensate when it makes the transition in temperature from one degree microkelvin to absolute zero
known and hypothesized about the
concept of absolute zero, the lowest
possible temperature (approximately -
5 459.4 degrees Fahrenheit).
Theoretically, at absolute zero matter
comes to a complete standstill, since
any motion would generate heat and
raise the temperature. However,
10 scientists are still uncertain about
exactly what happens to matter when it
reaches absolute zero. Does it simply
maintain its form, as if in a state of
suspended animation, or does it break
15 down into subatomic particles?
Scientists have some ideas about how
such matter might behave from studies
of both superconductivity (a state in
which atomic particles behave in an
20 unusually orderly manner, allowing
electrical current to flow with no
resistance) and superfluidity (another
abnormally orderly atomic state that
allows liquids to pass through solids). In
25 both states, particles and atoms move
practically in lockstep, allowing
phenomena that are usually prevented
by the randomness of atomic motion.
But few would venture to guess whether
30 matter continues along the same orderly
scale, or whether at absolute zero it
makes a quantum leap to a new state.
Recent breakthroughs have allowed
scientists to create near-absolute-zero
35 conditions in the laboratory. After
studying the new data, most physicists
now agree that, at absolute zero, atoms
will condense into a single entity, in
effect becoming one large atom. This
40 transition is known as Bose-Einstein
condensation. The question still
remains: will a Bose-Einstein
condensate behave in a super-orderly
manner in other hyper-cold states?
45 Some scientists theorize that its state
will be extremely unstable, while others
maintain that matter in absolute zero will
be tremendously stable because it will
be free from motion. Scientists have
50 created atmospheres as cold as one
microkelvin (one-millionth of a degree
above absolute zero), but have not
reached absolute zero itself: the task is
daunting, because the colder atoms get,
55 the more prone they are to soaking up
energy from any surrounding source,
thereby raising their temperatures.
Some pessimists in the field suspect
that it will be centuries before any group
60 of atoms can be chilled to a state of
absolute zero.
Q)Which of the following can be inferred from the passage about the relationship between the temperatures of absolute zero and one degree microkelvin?
(A)The formation of a Bose-Einstein condensate occurs at both temperatures, although the condensate is more stable at the temperature of absolute zero.
(B) For all practical purposes, the two are indistinguishable, since it would take many centuries for a group of atoms to cool to absolute zero.
(C)While scientists theorize that matter behaves differently at these two temperatures, no experimental evidence of these different behaviors as yet exists.
(D)At one degree microkelvin, matter is in a state of superconductivity, whereas at absolute zero it is not.
(E)Matter always assumes the form of a Bose-Einstein condensate when it makes the transition in temperature from one degree microkelvin to absolute zero
