A New Experiment Hopes to Solve Quantum Mechanics’ Biggest Mystery
https://www.smithsonianmag.com/science-n...180974132/
EXCERPT: The quantum revolution never truly ended. Beneath the world of classical physics, at the smallest scales, tiny particles don’t follow the usual rules. Particles sometimes act like waves, and vice versa. Sometimes they seem to exist in two places at once. And sometimes you can’t even know where they are.
For some physicists, like Niels Bohr and his followers, the debates surrounding quantum mechanics were more or less settled by the 1930s. [...] Now, nearly a century later, a growing number of physicists are no longer content with the textbook version of quantum physics, which originated from Bohr’s and others’ interpretation of quantum theory, often referred to as the Copenhagen interpretation. The idea is similar to flipping a coin, but before you look at the result, the coin can be thought of as both heads and tails—the act of looking, or measuring, forces the coin to “collapse” into one state or the other. But a new generation of researchers are rethinking why measurements would cause a collapse in the first place.
A new experiment, known as the TEQ collaboration, could help reveal a boundary between the weird quantum world and the normal classical world of billiard balls and projectiles. The TEQ (Testing the large-scale limit of quantum mechanics) researchers are working to construct a device in the next year that would levitate a bit of silicon dioxide, or quartz, measuring nanometers in size—still microscopic, but much larger than the individual particles that scientists have used to demonstrate quantum mechanics previously. How big can an object be and still exhibit quantum behaviors? A baseball won’t behave like an electron—we could never see a ball fly into left field and right field at the same time—but what about a nanoscale piece of quartz?
The renewed effort to pin down how matter behaves on an atomic level is partly driven by interest in technological advancements, such as quantum computers, as well as by increasing support for new theoretical physics interpretations. [...] The idea that particles could exist in multiple states as once unsettled Einstein and a few others. But many physicists ignore these fundamental questions of what actually happens and characterize their own attitude as a “shut-up-and-calculate” one, Maudlin says. “Very few physicists want to understand foundational issues in quantum mechanics. And they don’t want to admit that it’s a pretty scandalous situation.”
Those who do investigate the foundational realities of atomic matter, however, seem to agree there’s likely more going on than existing theories cover, even if it’s not clear yet exactly what happens on such miniscule scales. [...] But the data from previous quantum experiments still don’t point toward a single interpretation, making it hard to pick one as a more accurate picture of reality... (MORE - details)
Does nature have a minimal length?
https://backreaction.blogspot.com/2020/0...ength.html
EXCERPT: . . . The idea that the Planck length is a minimal length only came up after the development of general relativity when physicists started thinking about how to quantize gravity. Today, this idea is supported by attempts to develop a theory of quantum gravity, which I told you about in an earlier video.
In string theory, for example, if you squeeze too much energy into a string it will start spreading out. In Loop Quantum Gravity, the loops themselves have a finite size, given by the Planck length. In Asymptotically Safe Gravity, the gravitational force becomes weaker at high energies, so beyond a certain point you can no longer improve your resolution.
When I speak about a minimal length, a lot of people seem to have a particular image in mind, which is that the minimal length works like a kind of discretization, a pixilation of an photo or something like that. But that is most definitely the wrong image. The minimal length that we are talking about here is more like an unavoidable blur on an image, some kind of fundamental fuzziness that nature has. It may, but does not necessarily come with a discretization.
What does this all mean? Well, it means that we might be close to finding a final theory, one that describes nature at its most fundamental level and there is nothing more beyond that. That is possible, but. Remember that the arguments for the existence of a minimal length rest on extrapolating 16 orders magnitude below the distances what we have tested so far. That’s a lot. That extrapolation might just be wrong. Even though we do not currently have any reason to think that there should be something new on distances even shorter than the Planck length, that situation might change in the future... (MORE - details)
https://www.youtube-nocookie.com/embed/nyPdIBnWOCM
https://www.smithsonianmag.com/science-n...180974132/
EXCERPT: The quantum revolution never truly ended. Beneath the world of classical physics, at the smallest scales, tiny particles don’t follow the usual rules. Particles sometimes act like waves, and vice versa. Sometimes they seem to exist in two places at once. And sometimes you can’t even know where they are.
For some physicists, like Niels Bohr and his followers, the debates surrounding quantum mechanics were more or less settled by the 1930s. [...] Now, nearly a century later, a growing number of physicists are no longer content with the textbook version of quantum physics, which originated from Bohr’s and others’ interpretation of quantum theory, often referred to as the Copenhagen interpretation. The idea is similar to flipping a coin, but before you look at the result, the coin can be thought of as both heads and tails—the act of looking, or measuring, forces the coin to “collapse” into one state or the other. But a new generation of researchers are rethinking why measurements would cause a collapse in the first place.
A new experiment, known as the TEQ collaboration, could help reveal a boundary between the weird quantum world and the normal classical world of billiard balls and projectiles. The TEQ (Testing the large-scale limit of quantum mechanics) researchers are working to construct a device in the next year that would levitate a bit of silicon dioxide, or quartz, measuring nanometers in size—still microscopic, but much larger than the individual particles that scientists have used to demonstrate quantum mechanics previously. How big can an object be and still exhibit quantum behaviors? A baseball won’t behave like an electron—we could never see a ball fly into left field and right field at the same time—but what about a nanoscale piece of quartz?
The renewed effort to pin down how matter behaves on an atomic level is partly driven by interest in technological advancements, such as quantum computers, as well as by increasing support for new theoretical physics interpretations. [...] The idea that particles could exist in multiple states as once unsettled Einstein and a few others. But many physicists ignore these fundamental questions of what actually happens and characterize their own attitude as a “shut-up-and-calculate” one, Maudlin says. “Very few physicists want to understand foundational issues in quantum mechanics. And they don’t want to admit that it’s a pretty scandalous situation.”
Those who do investigate the foundational realities of atomic matter, however, seem to agree there’s likely more going on than existing theories cover, even if it’s not clear yet exactly what happens on such miniscule scales. [...] But the data from previous quantum experiments still don’t point toward a single interpretation, making it hard to pick one as a more accurate picture of reality... (MORE - details)
Does nature have a minimal length?
https://backreaction.blogspot.com/2020/0...ength.html
EXCERPT: . . . The idea that the Planck length is a minimal length only came up after the development of general relativity when physicists started thinking about how to quantize gravity. Today, this idea is supported by attempts to develop a theory of quantum gravity, which I told you about in an earlier video.
In string theory, for example, if you squeeze too much energy into a string it will start spreading out. In Loop Quantum Gravity, the loops themselves have a finite size, given by the Planck length. In Asymptotically Safe Gravity, the gravitational force becomes weaker at high energies, so beyond a certain point you can no longer improve your resolution.
When I speak about a minimal length, a lot of people seem to have a particular image in mind, which is that the minimal length works like a kind of discretization, a pixilation of an photo or something like that. But that is most definitely the wrong image. The minimal length that we are talking about here is more like an unavoidable blur on an image, some kind of fundamental fuzziness that nature has. It may, but does not necessarily come with a discretization.
What does this all mean? Well, it means that we might be close to finding a final theory, one that describes nature at its most fundamental level and there is nothing more beyond that. That is possible, but. Remember that the arguments for the existence of a minimal length rest on extrapolating 16 orders magnitude below the distances what we have tested so far. That’s a lot. That extrapolation might just be wrong. Even though we do not currently have any reason to think that there should be something new on distances even shorter than the Planck length, that situation might change in the future... (MORE - details)