Holometer rules out first theory of space-time correlations

December 4, 2015 by Andre Salles
A member of the Holometer collaboration works on the sensitive space-time measuring device, located at Fermilab in Illinois. Credit: Fermilab

The extremely sensitive quantum-spacetime-measuring tool will serve as a template for scientific exploration in the years to come.

There has never been anything like the Holometer.

Based at the U.S. Department of Energy's Fermilab in Illinois, the Holometer isn't much to look at. It's a small array of lasers and mirrors with a trailer for a control room. But the low-tech look of the device belies the fact that it is an unprecedentedly sensitive instrument, able to measure movements that last only a millionth of a second and distances that are a billionth of a billionth of a meter – a thousand times smaller than a single proton.

Our common sense, and the laws of physics, assumes that space and time are continuous. The Holometer challenges this assumption. We know that energy on the atomic level, for instance, is not continuous and comes in small, indivisible amounts. The Holometer was built to test if space and time behave the same way.

If they do, this would mean that everything is pixelated, like a . When you zoom in far enough, you see that a digital image is not smooth, but made up of individual pixels. An image can only store as much data as the number of pixels allows. If the universe is similarly segmented, and hence more blurry than we think, then there would be a limit to the amount of information space-time can contain.

The main theory the Holometer was built to test was posited by Craig Hogan, a professor of astronomy and physics at the University of Chicago and the head of Fermilab's Center for Particle Astrophysics. In a new result released this week after a year of data-taking, the Holometer collaboration has announced that it has ruled out Hogan's theory of a pixelated universe to a high level of statistical significance. This means the Holometer did not detect the amount of correlated holographic noise – quantum jitter – that this particular model of space-time predicts.

But as Hogan emphasizes, that's just one theory, and with the Holometer, this team of scientists has proven that space-time can be probed at an unprecedented level.

A scientist works on the laser interferometer at the heart of the Holometer experiment. Credit: Fermilab.

"This is just the beginning of the story," Hogan said. "We've developed a new way of studying space and time that we didn't have before. We weren't even sure we could attain the sensitivity we did."

The Holometer is a deceptively simple device. It uses a pair of laser interferometers placed close to one another, each sending a one-kilowatt beam of light through a and down two perpendicular arms, 40 meters each. The light is then reflected back into the beam splitter where the two beams recombine. If no motion has occurred, then the recombined beam will be the same as the original beam. But if fluctuations in brightness are observed, researchers will then analyze these fluctuations to see if the splitter is moving in a certain way, being carried along on a jitter of space itself.

According to Fermilab's Aaron Chou, project manager of the Holometer experiment, the collaboration looked to the work done to design other, similar instruments, such as the one used in the Laser Interferometer Gravitational-Wave Observatory (LIGO) experiment. Chou said that once the Holometer team realized that this technology could be used to study the quantum fluctuation they were after, the work of other collaborations using laser interferometers (including LIGO) was invaluable.

"No one has ever applied this technology in this way before," Chou said. "A small team, mostly students, built an instrument nearly as sensitive as LIGO's to look for something completely different."

The challenge for researchers using the Holometer is to eliminate all other sources of movement until they are left with a fluctuation they cannot explain. According to Fermilab's Chris Stoughton, scientist on the Holometer experiment, the process of taking data was one of constantly adjusting the machine to remove more noise.

"You would run the machine for a while, take data, and then try to get rid of all the fluctuation you could see before running it again," he said. "The origin of the phenomenon we're looking for is a billion billion times smaller than a proton, and the Holometer is extremely sensitive, so it picks up a lot of outside sources, such as wind and traffic."

If the Holometer were to see holographic noise that researchers could not eliminate, it might be detecting noise that is intrinsic to space-time, which may mean that information in our universe could actually be encoded in tiny packets in two dimensions.

The fact that the Holometer ruled out his theory to a high level of significance proves that it can probe time and space at previously unimagined scales, Hogan said. It also proves that if this quantum jitter exists, it is either much smaller than the Holometer can detect, or is moving in directions the current instrument is not configured to observe.

So what's next? Hogan said the Holometer team will continue to take and analyze data, and will publish more general and more sensitive studies of holographic noise. The collaboration already released a result related to the study of gravitational waves.

And Hogan is already putting forth a new model of holographic structure that would require similar instruments of the same sensitivity, but different configurations sensitive to the rotation of space. The Holometer, he said, will serve as a template for an entirely new field of experimental science.

"It's new technology, and the Holometer is just the first example of a new way of studying exotic correlations," Hogan said. "It is just the first glimpse through a newly invented microscope."

The Holometer experiment is supported by funding from the U.S. Department of Energy Office of Science. The Holometer collaboration includes scientists from Fermilab, the University of Chicago, the Massachusetts Institute of Technology and the University of Michigan.

Explore further: Do we live in a 2-D hologram? New Fermilab experiment will test the nature of the universe

More information: Search for Space-Time Correlations from the Planck Scale with the Fermilab Holometer, arXiv:1512.01216 [gr-qc] arxiv.org/abs/1512.01216

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big_hairy_jimbo
2.6 / 5 (5) Dec 04, 2015
Interesting.
The Michelson–Morley interferometer failed to discover an Ether.
Ligo and others have failed to discover gravitational waves.
The Holometer failed to discover Hogan's theory of a pixelated universe.

All interferometers. Is there something wrong with these devices or the concept?
EyeNStein
2.8 / 5 (4) Dec 04, 2015
The Devices and the concepts are rooted in relativity theories which were extrapolated from M&M's interferometer null aether result. Those theories have been tested proven and successfully applied (otherwise your GPS wouldn't work right and Muons wouldn't have relativistic lifetime extensions.)

Its my hypothesis that relativity goes deeper than we currently have theories for, and our concept of space time is still skewed by assumptions we haven't got rid of yet. I suspect that the hypothetical man in the free falling elevator (who cant measure gravity/acceleration) can't measure any gravity waves either, as his equivalence/relativity is not just a zero, first and second order (displacement, velocity and acceleration all null) effect.
axemaster
4.4 / 5 (10) Dec 04, 2015
Holometer collaboration has announced that it has ruled out Hogan's theory of a pixelated universe to a high level of statistical significance

This is not really surprising to me. I think that the idea of a "pixelated universe" is very naive - it makes the assumption that space exists independent of its contents. If you really think about it there's actually no convincing evidence that space (in its incarnation as an actual "physical" field) exists at all. The usual way of thinking is to treat space as a coordinate system, and calculate forces from it. But of course these equations are symmetric - you can instead treat the forces as fundamental, and derive space from them. And if you derive space in this manner, it's easy to see that a "pixelated universe" is just a fantasy, because any quantization would have to exist between each individual particle pair (rather than as a volume effect), and thus would show up as simple uncorrelated noise - likely unmeasurable.
richard_k
1 / 5 (1) Dec 04, 2015
Just musing...

I see no reason why anyone would choose to create a simulation(the universe) that was coded as a projected 2d array as opposed to a 3d array, anyone care to take me to task on that one.

If the Universe is a simulation which contains a 3D array, variables, and rules that govern the components of the array then I see no reason why you would see an ether or information transfer at such a fine level. It's also why you could potentially have entanglement i.e. non local variables in the array, which would sit quite comfortably in such a simulation. Such a system would work fine with special relativity as at the end of the day time is the relationship between the variables("quantum" information) of the 3D array.
richard_k
3 / 5 (2) Dec 04, 2015
With regards gravity and being a complete layman, can anyone tell me why the field that surrounds the electron is not considered the prime candidate for gravity.

Why can the electron's field not behave differently when it is bound up as part of an atom as opposed to being "free" i.e. moving and generating a magnetic field. This would explain why smashing protons together at Cern you would never see gravity as it is the field of the electron when bound with protons. I'd love to know what happens to this "field" when an electron becomes part of an atom. Can anyone provide me with a link that explains where the field of the electron goes to when it is part of an atom. It's strange that you can build an atom out of quarks and electrons but the field of the electron does nothing in this state. It doesn't make sense to me.
holographic_consciousness
4.4 / 5 (7) Dec 04, 2015
This break my heart. I waited for one year fro the result of this test. I wanted the Holometer to find evidence of pixelated universe. Either way we must continue on the process of science. Hogan has a great understanding of Quantum Mechanics and his Holometer idea was amazing invention. Good Job.
Grallen
2.3 / 5 (3) Dec 04, 2015
Wouldn't a universe, or even just a solar system, simulation be complicated enough that time would pass slower in the simulation than in the world simulating it? With our awareness of the universe both large and small growing every day, it would be exponentially increasing in load. Why would they keep the simulation running this long?

richard_k
4 / 5 (2) Dec 04, 2015
Grallen you said "With our awareness of the universe both large and small growing every day, it would be exponentially increasing in load."

No, you would only be simulating the interaction between quarks, gluons, and electrons and their field, etc. in each piece of the array. The number of electrons, quarks etc. is fixed/related to the amount the big bang created. If you wished to observe a part of the universe, in a picture format for example, you could just focus in on say on the part of the array that contains planet earth or a part of planet earth to visualise what would be happening.

I really don't understand enough about this article to realise what they are actually doing. I don't understand their experiment. Say the universe has a pixellation down to the plank level and each pixel is part of that 3d array how would their experiment have been so significant. I don't get it. I don't get how their experiment would have proved the universe is a 2d arra
ab3a
3.7 / 5 (3) Dec 04, 2015
All interferometers. Is there something wrong with these devices or the concept?


Like other things I read in the Annals of Improbable Research, at first I laughed. Then, I began to wonder. If the instrument is not measuring something with electromagnetic waves, perhaps our assumptions of how an electromagnetic wave fits in to space/time needs work?
OdinsAcolyte
3 / 5 (4) Dec 04, 2015
Reality is particulate at the Planck scale. Still too small to detect.
Our universe is only a reflection we perceive as the whole but in fact is just a part.
RealityCheck
5 / 5 (2) Dec 04, 2015
Consider: As in LISA interferometer for gravitational wave detection, this 'space-time' Holometer suffers not only from sensitivity-overwhelmed-by-unrelated-noise-perturbations flaw, but also from inherent-compensatory-&-noise-effects flaws; as whole setup is immersed in the same 'space-time' context as the laser-light-beams, end-pieces(mirrors) and beam-splitters(half-mirror/crystal?).

Hence anything that affects space-time context will also affect all parts equally.

In HOLOMETER, LASER LIGHT STREAM/QUANTA going through 'splitter' is 'locally/transiently' affected similarly. Also, relative to the hypothesized 'space-time pixels', the splitter is a MACRO-MASS with inertia shared amongst many atoms in a BOUND electro-magnetic matrix, so no individual 'pixel' component/contribution to that mass's behavior will show up at OVERALL SCALE of splitter. Also, any 'localized' pixelation affecting single atoms also affects laser quanta 'locally' too. So 'sensitivity' moot. Flawed.
Uncle Ira
2.1 / 5 (7) Dec 04, 2015
@ Really-Skippy. How you are Cher? I'm as good as a good Earthling could be me, thanks for asking.

As in LISA interferometer for gravitational wave detection, this 'space-time' Holometer suffers not only from sensitivity-overwhelmed-by-unrelated-noise-perturbations flaw, but,,,,,,,, and a whole of more stuffs too


Exactly. Just like you told us in the Clubhouse.

Hence anything that affects space-time context will also affect all parts equally.


That's right, you tell it to them Podna,

In HOLOMETER, LASER LIGHT STREAM/QUANTA going through 'splitter' is 'locally/transiently' affected similarly. Also, relative to the hypothesized 'space-time pixels', the splitter is a MACRO-MASS with inertia shared amongst many atoms in a BOUND,,,,,,,, and lot more good stuffs too.


You wasting your time on these couyons Cher.

In case maybe somebody is smart enough to understand, here is the good stuffs in the Clubhouse.

http://earthlingclub.com/

jsdarkdestruction
3.1 / 5 (8) Dec 05, 2015
This break my heart. I waited for one year fro the result of this test. I wanted the Holometer to find evidence of pixelated universe. Either way we must continue on the process of science. Hogan has a great understanding of Quantum Mechanics and his Holometer idea was amazing invention. Good Job.

Respectfully,it's good to be excited about science and learning but it sounds like you are getting a bit emotionally invested in theories. It's not healthy for you or science to do so.
thingumbobesquire
1 / 5 (2) Dec 05, 2015
This really boils down to an issue of the ontological premise of supposed stuff called "information." Bernhard Riemann's 1854 habilitation thesis addressed the issue of continuity versus discreteness at its most fundamental level. There is no final elemental physical stuff isolated and apart from human cognition. Rather there is an ongoing evolvability, if you will, of substance that is confined to interacting domains of the inert, biotic, and noetic. These realms all exhibit necessary singularities of discreteness and potential continuousness.
http://thingumbob...pot.com/
zaai
5 / 5 (2) Dec 05, 2015
Very interesting experiment and amazing how the team pulled it off!
One note with the conclusion that the experiment shows that no quantization of space and time was measured.
You can't draw that conclusion IMHO. The experiment only proves that this way of measuring doesn't show quantization of space and time. Finding nothing doesn't mean its not there, just that you were unable to find it.
Drawing the conclusion that no quantization exists assumes that all conditions to interpret the results of the experiment are fully measured and understood. Since this is leading edge science into an area where new things are discovered regularly, you cannot make this assumption and hence not draw the conclusion that quantization doesn't exist. A bit philosophical I agree but people to tend to jump to all sorts of conclusions way to easily.

indio007
3 / 5 (4) Dec 05, 2015
All interferometers. Is there something wrong with these devices or the concept?


Like other things I read in the Annals of Improbable Research, at first I laughed. Then, I began to wonder. If the instrument is not measuring something with electromagnetic waves, perhaps our assumptions of how an electromagnetic wave fits in to space/time needs work?

What's scary is how much "Scientific knowledge" relies on the interferometer.
richk
1 / 5 (4) Dec 05, 2015
i/dont/get/it.if/the/wavelength/of/light/is/greater/than/the/quantum/of/space/why/would/it/"jitter"?
baudrunner
5 / 5 (1) Dec 05, 2015
Andre Salles writes that Chris Stoughton tells us that
"The origin of the phenomenon we're looking for is a billion billion times smaller than a proton"
..but Andre, you told us that
But the low-tech look of the device belies the fact that it is an unprecedentedly sensitive instrument, able to measure movements that last only a millionth of a second and distances that are a billionth of a billionth of a meter – a thousand times smaller than a single proton
Why even do this experiment, right!?!?
Reg Mundy
2 / 5 (4) Dec 05, 2015
You can't measure a ruler using the same ruler.
Everything in the Universe we "observe" is in that Universe so can only measure RELATIVE to other things in that Universe.
These guys are trying to measure the building blocks using instruments made out of the same building blocks....
24volts
5 / 5 (1) Dec 05, 2015
How would they cancel out the jitter caused by particles popping in and out if existence in the beam? That seems like it would be a bit difficult.
my2cts
3 / 5 (2) Dec 06, 2015
"We know that energy on the atomic level, for instance, is not continuous and comes in small, indivisible amounts. "
This is incorrect. Atomic transitions can also be cause by absorption of multiple photons whose energies add up to the transition energy.

https://en.wikipe...sorption
EnricM
1 / 5 (1) Dec 06, 2015
Interesting.
[...]

All interferometers. Is there something wrong with these devices or the concept?


It's clearly a conspiracy of the Liberal anti-interferometric lobby!!
pepe2907
5 / 5 (1) Dec 07, 2015
Do we really know that energy is essentially quantified, or we just know that it's absorbed and excreted in portions by the specific forms of energy configuration we call matter /and more specifically - the forms of matter we are made of/?
And isn't almost all we know about "energy" considering just the form/s/ carrying electromagnetic force?
indio007
5 / 5 (2) Dec 07, 2015
So ... the measuring device is made up of protons and can measure a billion billionth of it's own size???

Ok someone show me the theorem that proves that is mathematically even possible.
sstritt
5 / 5 (1) Dec 07, 2015
1kW laser for an interferometer? Isn't that a bit much?
antialias_physorg
4.4 / 5 (7) Dec 07, 2015
Ok someone show me the theorem that proves that is mathematically even possible.

You measure the phase shift of the two beams.

(If you were awake during physics class in high school it is quite likely that you have seen a demonstration of this first hand. It's same effect you get with the double slit experiment: constructive and destructive interference)
BobSage
1 / 5 (1) Dec 07, 2015
Speaking from a software engineer's point of view, if I have to simulate a universe, the last thing I would do is simulate every particle in it. Way way too much processor and memory required. Basically impossible.

I would, instead, feed each player the data needed to create the experience he or she would be having in the particular position they were in. That is very easy for a processor to handle. That is, in fact, what multi player online games do. In not too long, in fact, we will be able to live in a virtual world just like the one we live in now created just that way.
charlimopps
1 / 5 (1) Dec 07, 2015
Bobsage - That's actually what they were investigating. Relativity and quantum physics seems to be telling us that most measurements do not have discrete results until an observation is made. The cat is both alive and dead, until you look. That suggests simulation. Our environment isn't drawn until we look at it.
indio007
3 / 5 (2) Dec 07, 2015
Ok someone show me the theorem that proves that is mathematically even possible.

You measure the phase shift of the two beams.

(If you were awake during physics class in high school it is quite likely that you have seen a demonstration of this first hand. It's same effect you get with the double slit experiment: constructive and destructive interference)

Not shit sherlock. How do you resolve the difference that's a billion billionth of a proton ?
You are aware an interference pattern needs to be projected onto MATTER right?
0.000000000000001 of a proton accuracy? Bullshit.
Bulbuzor
not rated yet Dec 07, 2015
So is it a billionth of a billionth of a proton or a meter? Both are mentionned in the article
Osiris1
not rated yet Dec 08, 2015
Refine that holometer to be 10^14 as sensitive and look again. Still think Hogan is right but need to go ALL the way to Planck scale. Believe our universe is a giant onion as the nanoscopic scales grow ever smaller......atoms....nuclei.....protons, etc......quarks.....preons....n1......n2...... ........nx. Each succeeding step smaller yielding ever more powerful fundamental forces to be found that we have not seen...yet. Our universe is energetic enough, but forces outside our universe in 'hyperspace' of many more dimensions of which our 'visible' universe is only a subset (leads to multiverse) may be many orders of magnitude greater and operate at ever smaller ranges.

That said, such research will require extreme amounts of power to operate, and be quite dangerous inasmuch as it could generate rips in spacetime with unpredictable effects. Our computers as they grow more powerful each decade per Moore's Law can show the way like it does with fusion modeling research.
Osiris1
not rated yet Dec 08, 2015
So it uses one microsecond timebase for movements up to 1 x (10^(-9))nanometers. Corresponds to one megahertz pulse frequency, about the clock speed of the old 6502 that powered the now ancient Apple ][+ personal computer. Old guys will remember that one...came out in 1978-9 and standard with a whole fourteen K of memory.

We have terahertz oscillators now and these are a million times faster so could look for the same movements as this one so will measure movements of up to 1 x (10^(-15))nanometers. Now increase that distance by putting the rig in space and extend the arms to 4 million km and use a higher laser power from an x-ray or blue ray source. Added benefit is that in space, gravitational forces on the light beams will cancel if the space rig is at Lagrangian points of the Earth-Moon-Sun system with the mirrors precisely 4 million km from it preserving geometrical relationships. This would get one to 1 x (10^(-21)) nanometers.
Maybe find gravitational waves too.
antialias_physorg
5 / 5 (3) Dec 08, 2015
How do you resolve the difference that's a billion billionth of a proton ?

By measuring interference. Note: not spatial interference. You just measure the light incident on a photodetector. While no gravity wave is passing the light intensity is very stable. But when a gravity wave passes you get shortening in one leg and lengthening in the other (and half a wave later the converse) - so the two beams start to interfere differently. You get a characteristic dip pattern in the light intensity (which is markedly different from noise in that it is symmetric). The amount of dip in intensity shows you how much the beams are out of phase, which directly translates to a relative change in distances in the legs.
Full description can be found here:
http://arxiv.org/...43v3.pdf

1kW laser for an interferometer? Isn't that a bit much?

Needed to minimize shot noise (due to quantized nature of light).
my2cts
not rated yet Dec 08, 2015
Relativity and quantum physics seems to be telling us that most measurements do not have discrete results until an observation is made.

I agree with the first sentence because you write "seems".
The cat is both alive and dead, until you look. That suggests simulation. Our environment isn't drawn until we look at it.

That is the paradox. Of course that cat is either alive or it is dead. Of course our environment exists whether we look at it or not.

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