Experiments Show The Effects of a Fourth Spatial Dimension
DAVID NIELD 6 JAN 2018
We're used to dealing with three physical dimensions and one extra dimension of time as we move through the Universe, but two teams of scientists have shown that a fourth spatial dimension could reach beyond the limits of up and down, left and right, and forwards and backwards.
As you might expect given this is bending the laws of physics, the experiments involved are partly theoretical and very complex, and touch on our old friend quantum mechanics.
By placing together two specially designed 2D setups, two separate teams of researchers - one in Europe and one in the US - were able to catch a glimpse of this fourth spatial dimension through what's known as the quantum Hall effect, a certain way of restricting and measuring electrons.
"Physically, we don't have a 4D spatial system, but we can access 4D quantum Hall physics using this lower-dimensional system because the higher-dimensional system is coded in the complexity of the structure," a researcher with the US-based team, Mikael Rechtsman from Penn State University, told Ryan F. Mandelbaum at Gizmodo.
"Maybe we can come up with new physics in the higher dimension and then design devices that take advantage the higher-dimensional physics in lower dimensions."
In other words, just as a 3D object casts a 2D shadow, scientists have managed to observe a 3D shadow potentially cast by a 4D object – even if we can't actually see the 4D object itself. That could unlock some new findings in the very fundamentals of science.
Thanks to some rather advanced calculations – which won the Nobel Prize for Physics in 2016 – we know that the quantum Hall effect points to the existence of a fourth spatial dimension.
What these new experiments do is give us a picture of the effects that this fourth dimension might have.
The European team's setup involved atoms cooled down close to absolute zero and placed in a 2D lattice through the user of lasers, described as "an egg-carton-like crystal of light" by the researchers.
With the addition of extra lasers, the team was able to implement a quantum "charge pump" to excite the trapped atoms and get them moving. Slight variations in the movement spotted by the researchers match up with how a 4D quantum Hall effect would ripple out – adding weight to the possibility that a fourth spatial dimension can be somehow accessed.
The US experiment also used lasers, this time to control light as it flowed through a block of glass. By manipulating the light to simulate the effect of an electric field on charged particles, again the consequences of a 4D quantum Hall effect could be observed.
Of course, we can't physically access this 4D world – we're stuck in 3D space – but scientists think quantum mechanics could somehow give us a picture of it, thus enhancing our limited understanding of the Universe.
Another way to think about it, courtesy of this video, is if we were video game characters from a 2D platform, and suddenly wandering around in a 3D game. Our perspective would stay 2D, but as we moved around we would see distortions and flips as the 3D world was folded into a 2D plane.
The same kind of distortions have been shown in this study, hinting at a bigger 4D world outside what we can see right now.
So we can't take a trip to the fourth spatial dimension just yet – but we've got more evidence that it's out there, and a better idea how how it works.
The team of researchers now wants to build on these studies to take a closer look, and to maybe explore some even more advanced physics along the way.
"I think that the two experiments nicely complement each other," one of the European researchers, Michael Lohse from the Ludwig-Maximilians University in Germany, told Gizmodo.
Meanwhile, I was just imaging the taste a meatball sub with mash potatoes and cheese in it...
US and European scientists 'photograph' mysterious FOURTH dimension in shock breakthrough
Since Albert Einstein developed the theory of relativity in 1905, the fourth dimension usually meant time.But, two teams in the US and another in Europe have shown the existence of a fourth spatial dimension.
Mikael Rechtsman from Penn State University said: "Physically, we don't have a 4D spatial system, but we can access 4D quantum Hall physics using this lower-dimensional system because the higher-dimensional system is coded in the complexity of the structure.
"Maybe we can come up with new physics in the higher dimension and then design devices that take advantage the higher-dimensional physics in lower dimensions." GETTY Two teams have shown the existence of a fourth spatial dimension In layman’s terms, 3D objects cast 2D shadows, so 4D objects should cast 3D shadows even if the 4D object is imperceivable.The two teams created two custom-designed, two-dimensional experiments to generate an instance of the quantum Hall effect, which restricts the movement of electrons which allows us both to perceive and measure them.
Researchers who studied the effect managed to win the 2016 Nobel Prize for Physics and three Nobel Prizes have been awarded for experimental and theoretical work for the effect.
The effect normally manifests itself in the boundary between two materials, where electrons can only move in two dimensions.
When a magnetic field is produced in a 90-degree line to the 2D plane it changes the behaviour of electrons which flow through it.
This can be further manipulated by reducing the temperature and increasing the voltage within the environment.
The greater the voltage and the larger the field, the more of a role quantum mechanics plays.
The reason for this is that the magnetic field generates a force acting at right angles to the direction of motion - the Lorentz force - which deviates the electrons.
But at low temperatures and very large magnetic fields, quantum mechanics starts playing a role which means the voltage no longer increases continuously but rather jumps in discrete steps.
The European team supercooled atoms close to absolute zero, which were then placed in a 2d lattice created using lasers.
They were then “excited’ using the additional laser to get them moving again.
The US team instead beamed a laser through a block of glass to simulate the effect of an electric field on charged particles. GETTY The two teams created two custom-designed, two-dimensional experiments Michael Lohse, one of the European researchers from the Ludwig-Maximilians University in Germany, said: "I think that the two experiments nicely complement each other.”
The quantum Hall effect can be understood as a topological phenomenon.
An example of Topology describes how many holes an object has and into what other shapes it can be transformed without cutting it.
Similar laws are responsible for the quantum Hall effect for electrons’ only being able to move along topologically well-defined paths. GETTY The quantum Hall effect can be understood as a topological phenomenon It was shown mathematically 20 years ago that comparable topological effects should also occur in four spatial dimensions.
Professor at the Institute for Theoretical Physics Oded Zilberberg said: "At the time, however, that was more like science fiction.“Right now, those experiments are still far from any useful application.”
Physicists can now investigate not just on paper, but also experimentally that phenomena occurring in four or more dimensions can have in our usual three-dimensional world.
Quasicrystals in metallic alloys are one example, which in three dimensions