Einstein's dream surpassed

Sep 02, 2011

(PhysOrg.com) -- A constant stabilization experiment of a quantum state has been successfully carried out for the first time by a team from the Laboratoire Kastler Brossel headed by Serge Haroche. The researchers succeeded in maintaining a constant number of photons in a high-quality microwave cavity. The results of their study are published in the online journal Nature on September 1, 2011.

The photon, the basic unit of light, can normally only be observed when it disappears. The eye absorbs photons, destroying them and translating the information they carry as it is recorded. However, this destruction is not indispensable. Four years ago, a team from the Laboratoire Kastler Brossel made a major breakthrough: observing, hundreds of times, a single and same microwave photon trapped in a box.

In their new work, the researchers have gone even further: they have succeeded in stabilizing a given number of photons in a “photon box”, a cavity formed of two superconducting mirrors. It is the first complete experiment of quantum stabilization. Generally speaking, stabilizations ensure the operation of the systems that surround us. In the case of an oven, its heating temperature is dependent on a set value: as long as the ideal temperature has not been reached, the oven continues to heat up then maintains its state according to the thermostat readings.

The transfer of these concepts to the microscopic quantum world comes up against an obstacle: the measurement – the thermometer – changes the state of the system. Quantum stabilization consists in a measurement performed through the injection of atoms, ultrasensitive probes, into the cavity. This measurement does not fix the number of photons, but provides a vague estimation. Like any quantum measurement, it however modifies the state of the cavity. A monitor – the thermostat – takes into account this information as well as the perturbation of the measurement and controls a conventional microwave source – the oven's heating elements. In this way, the cavity is taken or returned to a state where the number of photons has exactly the prescribed value.

Einstein had a dream: to trap a photon in a box for a period of around one second. This quantum stabilization has now enabled the LKB group to go even further in fulfilling this dream by maintaining, in a permanent manner, a given number of in the box. This experiment represents an important step in the control of complex quantum states.

Explore further: Scientists find way to maintain quantum entanglement in amplified signals

More information: Real-time quantum feedback prepares and stabilizes photon number states, C. Sayrin, et al., Nature, 1st September 2011.

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User comments : 24

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Isaacsname
not rated yet Sep 02, 2011
So this is what would be considered a true isolated system in thermodynamics ?
Ironhorse
5 / 5 (2) Sep 02, 2011
So this is what would be considered a true isolated system in thermodynamics ?


No, or they would have violated entropy. It sounds like they got a system to hold photons with the same quantum properties, ie. when the photons interact with the system boundary (not the measuring device, that is separate) they got the boundary to emit a photon with the same properties as the ones it interacted with. Notice they had to 'adjust the ... heating elements' to get this to work, so they essentially added energy, satisfying entropy.
Isaacsname
not rated yet Sep 02, 2011
So this is what would be considered a true isolated system in thermodynamics ?


No, or they would have violated entropy. It sounds like they got a system to hold photons with the same quantum properties, ie. when the photons interact with the system boundary (not the measuring device, that is separate) they got the boundary to emit a photon with the same properties as the ones it interacted with. Notice they had to 'adjust the ... heating elements' to get this to work, so they essentially added energy, satisfying entropy.


Ahh, ok, I get it. Thank you.
Callippo
3 / 5 (2) Sep 02, 2011
..the thermostat takes into account this information as well as the perturbation of the measurement and controls a conventional microwave source the oven's heating elements. In this way, the cavity is taken or returned to a state where the number of photons has exactly the prescribed value...
It's disputable, whether it's a true stabilization of (bunch of) photons. For example, the steady-state laser works at quasistable regime, in which the number of photons leaving the laser is balanced with newly added photons - so that the number of photons inside of lasing cavity remains the very same. But does it mean, these photons are really trapped inside of cavity?
stealthc
1 / 5 (4) Sep 02, 2011
sounds like a mind trick, I don't think this proves it either way. Just because it appears like one under this experiment doesn't mean they created one. Besides how do they know that the quantum state of the photons are totally the same when they are "re-balanced", here i see the temp and maybe the frequency is the same, what about other properties (such as spin orientation).
Pressure2
1 / 5 (3) Sep 02, 2011
What so unusual about accomplishing something like this? They inject a quantity of microwaves inside a cavity that has near perfect reflectivity at a superconducting temperature and it last for a period time before a measurable number of microwaves are absorbed.
kochevnik
1.4 / 5 (9) Sep 02, 2011
So this is what would be considered a true isolated system in thermodynamics ?
No, or they would have violated entropy.
Entropy is so 1800s. A relic of engineering more than science. Consider that the very definition of entropy posits a negentropic origin, which begs the question: What caused the original negentropy? Engineers design closed, symmetric systems within which entropy rises, but they are invariably attached to open systems where it is known that the 2nd law of thermodynamics need not apply. This dogmatic POV is responsible for the world's energy crisis.
bewertow
3 / 5 (6) Sep 03, 2011
So this is what would be considered a true isolated system in thermodynamics ?
No, or they would have violated entropy.
Entropy is so 1800s. A relic of engineering more than science. Consider that the very definition of entropy posits a negentropic origin, which begs the question: What caused the original negentropy? Engineers design closed, symmetric systems within which entropy rises, but they are invariably attached to open systems where it is known that the 2nd law of thermodynamics need not apply. This dogmatic POV is responsible for the world's energy crisis.


LOL what the hell are you talking about?
deepsand
3.3 / 5 (14) Sep 03, 2011
Might be a new kevinrtrs sock-puppet.
Erscheinung
3.4 / 5 (5) Sep 04, 2011
So this is what would be considered a true isolated system in thermodynamics ?
No, or they would have violated entropy.
Entropy is so 1800s. A relic of engineering more than science. Consider that the very definition of entropy posits a negentropic origin, which begs the question: What caused the original negentropy? Engineers design closed, symmetric systems within which entropy rises, but they are invariably attached to open systems where it is known that the 2nd law of thermodynamics need not apply. This dogmatic POV is responsible for the world's energy crisis.


LOL, ignorant of both political philosophy and basic science.
Erscheinung
2.3 / 5 (3) Sep 04, 2011
Might be a new kevinrtrs sock-puppet.


must be the same hand that controls the Vendecar sock-puppet.
deepsand
3.2 / 5 (11) Sep 04, 2011
Were that the case one would expect their respective posts to be more complementary of the other, rather than standing in opposition.
sinaphysics
not rated yet Sep 04, 2011
Is it possible someone explain this:

"In their new work, the researchers have gone even further: they have succeeded in stabilizing a given number of photons in a photon box, a cavity formed of two superconducting mirrors. It is the first complete experiment of quantum stabilization. Generally speaking, stabilizations ensure the operation of the systems that surround us. In the case of an oven, its heating temperature is dependent on a set value: as long as the ideal temperature has not been reached, the oven continues to heat up then maintains its state according to the thermostat readings."
ED__269_
1 / 5 (1) Sep 04, 2011
Possible?

The key word here is quantum stabilization. The ideal mirror doesn't exist, and this is also reflected in the words microwave-oven. The degree of loss at the reflection points must be known and compensated for.

Entropy shouldn't be associated with this article.

At the cavity walls, there must be energy balance otherwise the system cannot be considered a true quantum equilibrium. In other words, one could select the cavity walls as the system boundary and classify the system as a closed system as long as equilibrium remains true. The energy input of the microwave often should be considered needed to ensure integrity of the boundary.

Also, this experiment is particular to a predetermined wavelength (micro's) and frequency, though it should still work as a general principle.
ED__269_
1 / 5 (1) Sep 04, 2011
Also, because the compenstation has been made, schrodingers cat might now be classed at the moment of death? Perhaps it is more important to identify the moment when the machine releases the gas.
akulkoomal
1 / 5 (4) Sep 07, 2011
Traping a photon in a box for a period of time proves nothing. To understand this something else need to be understood, not yet undestood by present science. In the darker side of the universe the movement of sun light even comes to an end. All the moon journeies failed to find out what really is the moon and what kind of environment prevails there,which is totally different from this earth. The environment of moon changes continuously if not physical but in the form of energy.
kochevnik
2.6 / 5 (5) Sep 07, 2011
LOL, ignorant of both political philosophy and basic science.
How so? Blanket statements like yours are red flag for ignorance. Or are we on the "it must be true because Erscheinung says so" school of thought?
kochevnik
3 / 5 (4) Sep 07, 2011
LOL what the hell are you talking about?
Discussions of entropy posit negentropy as a prerequisite. Possibly this ties into fanciful notions of some imaginary fairy creating the zero entropy world. It rings of back-door creationism.
SR71BlackBird
3 / 5 (2) Sep 07, 2011
This is very interesting indeed! Quantum computing is one step closer to reality! On a side note: negentropy is a statistical phenomenon representing the 'distance' of signal to normality. Schrodinger used the term negative entropy to describe processes involved in living organisms. For example, a dead animal is at higher entropy than an animal which is alive. When the animal consumes its dead prey, it is essentially consuming something of higher order and creating something of less order (i.e. energy used in cell division). Obviously kochevnik is a crackpot who appears to have no real understanding of physics. As far as the 2nd law of thermodynamics goes, it doesn't apply to open systems because it is defined as the process of equilibrium for an isolated system. It just simply means that processes follow a certain direction (or arrow of time).
TJ TOCCO
1 / 5 (2) Sep 07, 2011
I made a major discovery, Antares light speed is 90% faster than the speed of light from the earth. Thats light speed as it leaves from the star Antares is moving 9 times faster than that of light which leaves from the earth.
TJ TOCCO
1 / 5 (2) Sep 07, 2011
I made a major discovery, Antares light speed is 90% faster than the speed of light from the earth. Thats light speed as it leaves from the star Antares is moving 9 times faster than that of light which leaves from the earth.
kochevnik
2.3 / 5 (3) Sep 07, 2011
kochevnik is a crackpot who appears to have no real understanding of physics.
If I'm the crackpot, you're the fool just repeating what I said earlier, while contributing nothing novel. Thanks for agreeing with me.
SR71BlackBird
3.7 / 5 (3) Sep 08, 2011
kochevnik is a crackpot who appears to have no real understanding of physics.
If I'm the crackpot, you're the fool just repeating what I said earlier, while contributing nothing novel. Thanks for agreeing with me.


You're questioning a general theory of thermodynamics by stating that their must be some sort of negentropy resulting from the big bang. What you fail to understand is that 'negative entropy' is not true in that sense. You're taking the definition out of context. And then you proceed to criticize engineers for not understanding how 'open systems' behave due to your so called negentropy. Start by picking up a physics textbook. If you still believe everyone's wrong, then I suggest you write a paper on the topic of negentropy at the beginning of the universe and then have it be peer reviewed. Otherwise, you're still a crackpot.
ED__269_
1 / 5 (1) Sep 14, 2011
looking at when the machine released the gas does nothing from a physics perspective. the phenomenological edge is interesting & unique tho...

The real questions are Why? and How?

-----
given general understanding ,,,

entropy should be exactly cancelled at the interface/mirror and points of interface/registration since their boundary is uniquely known thus to achieve dynamic stabilization over general

pinpointing the angle, point,& moment of exchange... a hard one: so, who's up for ray tracing?