Neutrons are subatomic particles that have no electric charge, unlike protons and electrons. That means that while the electromagnetic force is responsible for most of the interactions between radiation and materials, neutrons are essentially immune to that force.
The traveling salesman problem is considered a prime example of a combinatorial optimization problem. Now a Berlin team led by theoretical physicist Prof. Dr. Jens Eisert of Freie Universität Berlin and HZB has shown that a certain class of such problems can actually be solved better and much faster with quantum computers than with conventional methods.
Quantum computers use so-called qubits, which are not either zero or one as in conventional logic circuits, but can take on any value in between. These qubits are realized by highly cooled atoms, ions, or superconducting circuits, and it is still physically very complex to build a quantum computer with many qubits. However, mathematical methods can already be used to explore what fault-tolerant quantum computers could achieve in the future.
“There are a lot of myths about it, and sometimes a certain amount of hot air and hype. But we have approached the issue rigorously, using mathematical methods, and delivered solid results on the subject. Above all, we have clarified in what sense there can be any advantages at all,” says Prof. Dr. Jens Eisert, who heads a joint research group at Freie Universität Berlin and Helmholtz-Zentrum Berlin.
The advanced civilization in my story have harnessed the power of many of the stars in their galaxy and using them for different purposes, one being Matrioska brains. Some of these super computers will be to run the AI in the real world as well as for other calculations, Others will be to run detailed virtual worlds. The earliest Simulations will be Computer simulated worlds with artifical life within but later the advanced species will try to create simulations to the subatomic level.
It has been stated that a Matrioshka brain with the full output of the sun can simulate 1 trillion to a quadrillion minds, how this translates to how much world/simulation space can exist and to what detail i am not sure. I believe our sun’s output per second is $3.86 \cdot 10^{26}$ W and our galaxies is $4\cdot 10^{58} \ W/s$, although with 400 billions stars in our galaxy I am not sure how of that energy is from other sources than the stars.
If we look past the uncertainty of subatomic partcles we have $10^{80}$ particles in a space of $10^{185}$ plank volumes in our observable universe, if we use time frames of $10^{-13}$ seconds this gives $10^{13}$ time frames per real second. With $10^{80}$ particles we can have $10^{160}$ interactions for a full simulation but a simulation where only the observed/ observable details needs to be simulated can run off much less computing.
Physicists in the MIT-Harvard Center for Ultracold Atoms (CUA) have developed a new approach to control the outcome of chemical reactions. This is traditionally done using temperature and chemical catalysts, or more recently with external fields (electric or magnetic fields, or laser beams).
MIT CUA physicists have now added a new twist to this: They have used minute changes in a magnetic field to make subtle changes to the quantum mechanical wavefunction of the colliding particles during the chemical reaction. They show how this technique can steer reactions to a different outcome: enhancing or suppressing reactions.
This was only possible by working at ultralow temperatures at a millionth of a degree above absolute zero, where collisions and chemical reactions occur in single quantum states. Their research was published in Science on March 4.
New insights into near-Earth space’s hazardous environment could revolutionize space weather prediction, driven by collaborative international research.
A challenge to space scientists to better understand our hazardous near-Earth space environment has been set in a new study led by the University of Birmingham.
The research represents the first step towards new theories and methods that will help scientists predict and analyze the behavior of particles in space. It has implications for theoretical research, as well as for practical applications such as space weather forecasting.
The results, continuing the legacy of late Columbia professor Aron Pinczuk, are a step toward a better understanding of gravity.
A team of scientists from Columbia, Nanjing University, Princeton, and the University of Munster, writing in the journal Nature, have presented the first experimental evidence of collective excitations with spin called chiral graviton modes (CGMs) in a semiconducting material.
A CGM appears to be similar to a graviton, a yet-to-be-discovered elementary particle better known in high-energy quantum physics for hypothetically giving rise to gravity, one of the fundamental forces in the universe, whose ultimate cause remains mysterious.
A new theoretical analysis connects the results of high-energy particle experiments at the Large Hadron Collider with three-proton correlations inside nuclei.
A nanoresonator trapped in ultrahigh vacuum features an exceptionally high quality factor, showing promise for applications in force sensors and macroscopic tests of quantum mechanics.
Nanomechanical oscillators could be used to build ultrasensitive sensors and to test macroscopic quantum phenomena. Key to these applications is a high quality factor (Q), a measure of how many oscillation cycles can be completed before the oscillator energy is dissipated. So far, clamped-membrane nanoresonators achieved a Q of about 1010, which was limited by interactions with the environment. Now a team led by Tracy Northup at the University of Innsbruck, Austria, reports a levitated oscillator—a floating particle oscillating in a trap—competitive with the best clamped ones [1]. The scheme offers potential for order-of-magnitude improvements, the researchers say.
Theorists have long predicted that levitated oscillators, by eliminating clamping-related losses, could reach a Q as large as 1012. Until now, however, the best levitated schemes, based on optically trapped nanoparticles, achieved a Q of only 108. To further boost Q, the Innsbruck researchers devised a scheme that mitigated two important dissipation mechanisms. First, they replaced the optical trap with a Paul trap, one that confines a charged particle using time-varying electric fields instead of lasers. This approach eliminates the dissipation associated with light scattering from the trapped particle. Second, they trapped the particle in ultrahigh vacuum, where the nanoparticle collides with only about one gas molecule in each oscillation cycle.
The full collection of top quark mass measurements by the CMS experiment! 🗝
What’s the best way to pin down the exact mass of this enigmatic particle? Discover the diverse strategies perfected by CMS over the last decade:
When it comes to top quark mass measurements, the CMS collaborati on has the largest and most complete collection of publication-quality results, cov ering a wide range of methods and approaches. In a recent review paper, an overview is given of all top quark mass measurements published by CMS so far. In the quest to pin down the exact mass of this enigmatic particle, different methods were developed and perfected over the last decade.
IceCube Researchers reported on the stringent constraints on potential quantum fluctuations of spacetime itself.