Late morning. Carol is going to lunch with
retired Blue Ash teachers at Montgomery Inn. Bob Hope used to say they had the
best ribs in the world. They are good ribs. The last time I ate there was in
2001 with a former student at Indian Hill. He had just bought my first book,
Stuck, and wanted me to sign it. He brought me a Cuban cigar to celebrate.
1037
hours. Doug sent me an article yesterday that is very interesting, at least to
me in concept. Here it is. [My old friend, thank you John Douglas Goss.]
**
**
Below Absolute Zero: Negative Temperatures
Explained
Absolute zero, or 0 degrees Kelvin, is the
temperature where all motion stops. It's the lowest limit on the temperature
scale, but recent news articles have heralded a dip below that limit in a
physics lab. Is absolute zero less absolute than we thought? Read on to find
out.
Researchers at the Max-Planck Institute for
Quantum Optics and the Ludwig-Maximilians University Munich worked with a Bose
Einstein Condensate of about 112,000 very cold potassium atoms (39K). A Bose
Einstein condensate is made up of atoms that can occupy the same state.1
They put these atoms in an optical dipole
trap.1 The dipole trap confines the atoms and keeps them together. They then
used a tunable three-dimensional optical lattice that acts like a crystalline structure
for the potassium atoms to reside in and creates an associated energy band
structure.1
The optical lattice consists of a bunch of
laser beams set to create a standing wave that acts like a lattice structure
for the potassium atoms to be in. The potassium atoms in this lattice structure
remain in their lowest internal energy state, but they have an associated band
structure. The lattice confines the motional states of the atoms to this lowest
energy band; however, this band consists of many states (momenta states) for
each atom.
The researchers observed that the atoms could
all be in their lowest energy band level and very near to the lower edge of
that energy band level. Consequently, the system was extremely ordered (the
amount of order is key to this) and, as you might expect, very cold. Keeping
the atoms in this low-energy state led to a temperature of only a few
billionths of a Kelvin.1
This situation resembles placing a bunch of balls into a small valley, where
it's extremely unlikely for them to roll out.3
By very suddenly turning the valley of the
optical lattice into a hill, the researchers essentially “flipped” the entire
system around, causing the atoms to go into the upper edge of their lowest
energy band. This is akin to turning a stable valley into a stable hill. This
new “hill” is very stable, and the atoms would not roll off the hill to another
energy state. In this situation the atoms are very ordered, cannot go to
another energy level, and have a negative temperature value!
Below is an image of the
momentum distribution at negative temperatures of the potassium atoms in the
optical lattice. The momentum is proportional to the kinetic energy (motion
energy) of the atoms, and the peaks show the maximum kinetic energy. The
negative temperature states are very stable, and the atoms do not go to lower
motional energy states.1
What is Temperature Anyway?
In an everyday sense, temperature describes
an objects warmth or coolness. In science class, we are told that the
temperature of an object is defined as the average kinetic energy (motion
energy) of all the atoms that make up an object. The more the atoms that make
up an object jiggle around (more motion energy), the warmer the object is.
It makes sense that if a warmer object is
next to a cooler object, heat energy will transfer, from the warmer object to
the cooler object. Think about those moving particles colliding with the cooler
ones next to it (heat transfer by conduction). Similarly, the warmer particles
that are in a higher energy state go to a lower one, radiating an
electromagnetic wave in the infrared region and another atom absorbing that
radiation (heat transfer by radiation).
Two objects of different temperatures
eventually will reach a common temperature somewhere between the warmer
object’s initial temperature and the cooler object’s initial temperature.
But there are other types
of temperatures and other definitions of temperature. The one of importance for
“below absolute zero” has to do with a definition used in thermodynamics and
statistical mechanics. In thermodynamics, temperature is a macroscopic
property, and the microstates of the system determine this and other
properties.
If just one of the 100 atoms in this system
exists in the higher energy state then there are 100 ways to do this. In this
case, the entropy is log(100) = 2. Recall that the researchers used about
112,000 potassium atoms.
This means that entropy for this system is
maximized when half of the atoms are in the higher energy state and half are in
the lower energy state. If we reach the other extreme where all of the atoms
are in the excited state, then there is only one way to do this and the entropy
is again zero.
In statistical mechanics and thermodynamics,
temperature is defined as follows:
1/temperature
= change in entropy/change in energy
For our hypothetical system of 100 atoms with
only two energy states, there is an upper and lower bound of energy, and the
entropy of the system equals zero at these boundary limits. This definition of
temperature can go from positive infinity to negative infinity. The temperature
makes a discontinuous jump at the point where the entropy changes from an
increasing value to a decreasing value.
The temperature for all the atoms in their
ground state is zero. This is like a bunch of balls sitting in a valley.3
As energy is added to the system, some of the
atoms go to the higher energy state, the entropy increases, and the temperature
increases. This is like moving some balls out of the valley and onto the hill.
As more energy is added, more atoms go to a
higher energy level. The temperature approaches positive infinity as the
entropy nears its maximum, which occurs when half of the atoms exist in the
upper state and half are in the lower state. In the hill/valley analogy, half
of the balls would be in the valley and half would be on the hill.3
Still adding more energy, just as you reach
the state of half the atoms being in the upper state and half in the lower
state and pass it, the entropy of the system decreases. This results in the
temperature discontinuously jumping from positive infinity to negative infinity
(right at the halfway mark). This transition resembles the jump from having
just less than to just more than half the balls on the hill and half in the
valley.
As the system reaches its
maximum energy state, the atoms all are in their upper energy state, the
entropy goes to zero, and the negative temperatures increase, approaching zero.
This is like all the balls being very stable on the hill, and not being able to
fall off the hill.3
Does Negative Mean Colder?
It is important to note that the negative
temperature region, with more of the atoms in the higher allowed energy state,
is actually warmer than the positive temperature region. If this system were to
be brought into contact with a system containing more atoms in a lower energy
state (positive temperatures) heat would flow from the system with the negative
temperatures to the system with the positive temperatures. So negative
temperatures are warmer! And all this has to do with the how we define
temperature.
One result from this experiment is that when
the gas of potassium atoms (which happens to be a Bose Einstein Condensate) is
experiencing negative temperatures, it is also experiencing negative pressure.1
If the pressure were not negative, then these highly attractive potassium atoms
would collapse on each other.
This idea of an attractive system not
collapsing is similar to the universe wanting to collapse due to the attractive
nature of mass. However, the universe is expanding according to all our
measurements and scientists have determined that something must be there to
cause it not to collapse.
Scientists have called this something “dark
energy,” because we can’t detect it. The researchers believe that perhaps the
results of negative pressure can give insights into the ideas of dark energy,
or a non-collapsing universe.
The researchers have also listed a number of
research areas that the results of this experiment suggest. These include
studies of: the Mott insulator transition, the parameters in the Hubbard model,
and many-body systems.1
The Mott insulator transition is the
transition between a material acting as an insulator or conductor of
electricity. This transition usually occurs at low temperatures and is related
to interactions between electrons. The Hubbard model is used to describe the
transition between conducting and insulating systems.
From: Physics Central
** **
There
is a line of logic in the article that I am attracted to but I will have to
re-read it several more times.
The line of logic has to do with
"flipping". Perhaps you are thinking of a computer-like device that
uses the 'flipping' instead of zero's and one's. Post. - Amorella
Thank you, Amorella.
You were going to say "What a time saving
device you are!" - Amorella
A slip of the fingers. I stopped
myself and deleted.
Why?
Because 'device' made you a 'thing'
and imagination or not, you are not a 'thing'.
What am I then? - Amorella
Well, (I can't help it) I think of you
as a Betweener from the GemNest. I know 'GemNest' is for use in the books, in
fiction, but to me you are real. The straight forward example is the
"flipping" paragraph. You are real enough to have written me three
books and are rewriting them presently. For a writer such as myself you are
real enough. I don't care what anybody says. - rho
Signed, no less. - Amorella
It's the truth, Amorella. It is not
the truth 'out there' it is the truth 'in here'. (1101)
1249
hours. I just watched the first two episodes of "Touch" (I had
watched the first hour last night). We all see connections to things, people,
events, because our minds are built to see connections and to sort them out.
Perhaps it is built in because our thought patterns are built on connections.
However, in the second episode, the girl, Amelia, I think her name is, she
began reading To Kill a Mocking Bird at a pace similar to that pace I read at
for years. My students loved to see me read so quickly. The difference is that
I read one, two or three paragraphs as a single sentence and I remembered gulps
of thought, essentials, but not specifics. The girl in the story has a
photographic memory and I have very little memory at all. I am thinking that if
a former student was watching that show sheorhe may remember me in the process.
This is how connections work in the real world. "Touch" is developing
similar to "24" in terms of pace. I like that. Quick and you have to
keep focused.
You actually articulated your speed-reading
abilities of the old days. I am surprised you did so without my help. -
Amorella
Reading automaticity, as I've said
before, I have been told that the ability is similar to what goes on in the
mind of a working simultaneous translator. It was self-taught probably
in the sixth or seventh grade and I became better at it through practice. It was
a wonderful and fun ability when grading essay papers, at least thirty-four years
worth of such papers.
Let's work on Pouch 12 and be done with it
so we can move on. - Amorella
1343 hours. I have some 300 added
words and must cut about half.
Take a break. We will go back through what
you already have to eliminate what is unneeded. - Amorella
You are at Kroger's
on Tylersville waiting for Carol after you both had a Graeter's treat. You just
finished Pouch 12 while waiting on her. Drop it in here.
***
Diplomatic Pouch 12 ©2013 rho, nfd
Blake glanced at his sister, wondering what she was thinking.
Pyl
looked over at the plane. No apparent damage. No problems when they became
airborne when the wheels left the road. Where is that road now, only moments
later it seems, and the road, the county airport, Ohio, Lake Erie -- where are
they? All I have here are my husband, my brother, and Daddy's plane.
Justin
felt almost uncontrollably alone. We don't know where we are and until we do we
cannot hope to escape these people. Are they terrorists? Our plane is perhaps
more important than we are. Do they want our plane to use as a terrorist
weapon? Surely we are being duped. Pyl and Blake are my responsibility at this
point. I have to come up with a plan.
"Again,
we welcome you onboard our vessel," assured Friendly in both manner and
voice. "Ship also welcomes you. We will show you selections of our vessel.
Then you can see where you are."
"Come
this way," directed Yermey. "We can climb the flight of stairs to the
main deck. Where we are is in the annex."
"What
you may call a basement," added Hartolite.
"Or
a storage area," said Friendly. "Follow Yermey. Yermey one step at a
time for our guests please."
Blake
carefully observed the setting first by counting the stairs, there were
twenty-two. The room appeared large and hospital clean in perhaps a forty to
fifty-foot square. In the dim light he could see machinery set at an angle of
about a thirty-degree tilt off center. Rather than seen the large box of
machinery, which towered up perhaps fifteen feet straight on he saw the box on
angle. 'I cannot tell,' he thought, 'how wide it is. It almost appears to be an
optical illusion.'
"Come
ahead, this way," directed Yermey. "Over to this area where we can
observe better."
Blake
followed mostly out of polite routine as if he were on a tour of a
manufacturing plant. A whiff of acidic scent reminded him of being in a factory
that molded exothermic sleeve forms used in the construction of steel castings,
but the ground had blended grass growing on it just as the Annex had. However
the grass floor felt short and soft, like he was walking on a golf green.
Shortly, Pyl and Justin stood beside him as Friendly and Hartolite walked
around to their left and stood next to Yermey.
The
six were elevator close together looking into the room from a new angle. No one
could see the door they had entered from. They could see no other entrance or
exit. The walls and ceiling slowly illuminated to an eye comfort level where
all could better view the space and what filled it.
I
am standing in the southeast corner of the room. We entered near the southwest
corner. Blake's eyes focused on the first thing he saw upon entering the
control room -- the two-stacked black boxes in the northwest corner from the
entrance. The size and shape reminded him of two top and bottom washer dryer
combinations with round see through side windows to the front of both. Each
window was surrounded by a four inch or so aluminum colored band. The boxes
were otherwise clean of buttons or dials. 'I estimate it is six to seven feet
high and three and a half feet in width.'
His
eyes moved east along the north wall to a second set of aluminum colored
metallic or plastic boxes set beside one another. On the horizontal rather than
the vertical they appear the same size and clean only the windows, similar in
size to the other machine have a square with rounded corners windows.
On
the northeast corner is a large blue metallic-like box the size of a large
refrigerator only a couple feet taller. It has one large oval window with an
aluminum-like band surrounding. The height of the oval is over seven feet and
it drops to within two feet of the bottom of the box. The width of the oval
band is within a couple of inches of the sides of the machine. I have no idea
what these machines do. There are no tables or chairs or desks. I wonder what
is on the other side of those windows. Blake's thoughts were interrupted.
Friendly's
teacher voice said, "We are all here. Where would you like me to
begin?"
Blake
replied, "I see many box-like in the room. Please start with the one in
the northwest corner." He pointed, "The two black stacked boxes, they
look like stacked washing machines."
769 words
***
1500 hours. Glad that is completed.
Now I go through the process of combining three chapters as a sub-unit as well
as Sentence descriptions of each chapter for reference. I am glad for this
reference section. It is too much to remember. I couldn't remember it in any
case. It takes most of my focus energy to have you write it Amorella.
You just added a document titled 'Robotics'
change this to Pouch 13 and file according. Post when convenient. - Amorella
1611 hours. We just returned from a
short time at Pine Hill Lakes Park. I worked the summaries up and Carol
balanced the checkbook.
2048
hours. We watched "The Mentalist" and "Bones" and snacked
on left over Papa John's pizza for supper. I finished the updates on the
various summaries and updated my flashdrive. I need up update iCloud and my
external hard drive also to keep everything in sync.
Tomorrow we begin the blog with the updated
near final draft chapters ten, eleven and twelve. We are more than half done
with the first re-write orndorff. Have you thought more about having it
published? - Amorella
No.
You are thinking that it would be very good
to actually see the final in a physical form, something you can hold in your
hands, something with physical dimensions and weight. The reason for this is
that as much as you love the abstract you also love the real world. - Amorella
You drew it out of me. Of course I
would think about it since you mentioned it. I was not thinking about it
before. Sometimes nothing is in my head, nothing at all. (2100)
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