Description of electrons as particles and waves.
Can cells think? | Michael Levin
Michael Levin, a developmental biologist at Tufts University, challenges conventional notions of intelligence, arguing that it is inherently collective rather than individual.
Levin explains that we are collections of cells, with each cell possessing competencies developed from their evolution from unicellular organisms. This forms a multi-scale competency architecture, where each level, from cells to tissues to organs, is solving problems within their unique spaces.
Levin emphasizes that properly recognizing intelligence, which spans different scales of existence, is vital for understanding life’s complexities. And this perspective suggests a radical shift in understanding ourselves and the world around us, acknowledging the cognitive abilities present at every level of our existence.
Is science about to end? | Sabine Hossenfelder
In his 1996 book “The End of Science”, John Horgan argued that scientists were close to answering nearly all of the big questions about our Universe. Was he right?
The theoretical physicist Sabine Hossenfelder doesn’t think so. As she points out, the Standard Model of physics, which describes the behavior of particles and their interactions, is still incomplete as it does not include gravity. What’s more, the measurement problem in quantum mechanics remains unsolved, and understanding this could lead to significant technological advancements.
Ultimately, Hossenfelder is optimistic that progress will be made in the next two decades, given the current technological advancements in quantum technologies and quantum computing.
How Nobel-Winning Physics Experiments Led to Quantum Computing | Tech News Briefing Podcast | WSJ
This year’s Nobel Prize in Physics was awarded to three scientists for their work in quantum computing.
WSJ science reporter Eric Niiler joins host Zoe Thomas to discuss their work and what it means for the future of superfast computers and encrypted communications.
Chaos: The Science of the Butterfly Effect
I have long wanted to make a video about chaos, ever since reading James Gleick’s fantastic book, Chaos. I hope this video gives an idea of phase space – a picture of dynamical systems in which each point completely represents the state of the system. For a pendulum, phase space is only 2-dimensional and you can get orbits (in the case of an undamped pendulum) or an inward spiral (in the case of a pendulum with friction). For the Lorenz equations we need three dimensions to show the phase space. The attractor you find for these equations is said to be strange and chaotic because there is no loop, only infinite curves that never intersect. This explains why the motion is so unpredictable – two different initial conditions that are very close together can end up arbitrarily far apart.
How Electricity Actually Work
Although the video does indeed point out that the electrons arrange themselves to establish the necessary fields in the wire, the treatment of the electrons thereafter is set aside for a preference of “the field”. However, as the electrons begin to drift, the only way for the field to maintain its necessary configuration is for the electrons to also continuously shift and move to maintain that field. Guess what? That also requires energy! Energy can also be stored in the charged particle configuration! In other words, if the “energy is in the field”, that energy would quickly dissipate and the field alone could not power the circuit unless the charges continuously rearranged themselves to maintain that field throughout the circuit. The field would not exist, or at least the necessary field to do continuous work would not be maintained without the flow of electronics, the current. Thus the current remains just as fundamental a part of the circuit as the field
The interesting engineering behind the SHAPE of Train wheels
Have you ever wondered why the train wheel shape is conical, not straight. Let’s explore this simple, but genius invention in detail.
How do we know the universe is quantum? What if it wasn’t?
What do we think the universe is quantum? What if the universe was not quantized?
Classical mechanics was doing just fine after Isaac Newton reduced nearly all mechanical phenomena to a single powerful equation: F=MA, James Clerk Maxwell also solved the mystery of electricity and magnetism. Classical physics is continuous. This means you can always keep dividing things into smaller pieces. But scientists realized that classical physics had some major flaws because certain phenomena could not be explained, like the color of a hot glowing body.
In 1900, Lord Rayleigh and James Jeans had used experimental data to come up with a law for how all objects emit electromagnetic radiation. The problem was that according to their theory a black body will send out energy in any frequency range allowed by the temperature. But for very energetic objects at temperatures above 5000 Kelvin, their theory predicts that the object should radiate away all its energy until it reaches absolute zero. It is called the ultra-violet catastrophe.
The solution to this problem marked the end of the classical world and the beginning of the quantum world. In 1900, Max Planck had come up with an equation to explain black body radiation. He treated radiation as being quantized, released only in discrete quanta of energy. So the emission of radiation was limited to quanta of energy, proportional to a Planck’s constant. E=hf, where the quanta of energy, E, is equal to the frequency f times Planck’s constant.
Another phenomenon that only quantum mechanics could explain was why an electron does not lose all its energy when orbiting a nucleus. If electrons orbit around the nucleus, then their circular motion means that they are constantly accelerating. But an accelerating electron means that it must be emitting photons, which means it must be losing energy. This would mean that the electron would continuously lose its orbital energy, and eventually hit the nucleus. So atoms could not exist.
Niels Bohr solved the problem by showing that only special orbits are allowed around the nucleus where the angular momentum of the electron is a whole number multiple of Planck’s constant over two pi. Light is only emitted or absorbed when electrons jump from one orbit to another.
Now to fully grasp our quantized world, we also need to account for special relativity. It was realized that the Schrodinger equation is wrong because it does not treat space and time equally. Paul Dirac fixed this problem by reformulating Schrodinger’s equation to threat space and time equally. This became the =Dirac Equation.
His equation, and later others, do not quantizing objects, but they quantize fields. And this gave rise to quantum field theory, or QFT. In QFT, particles are treated quantizations of fields. This allows us to treat space and time equally such that it satisfies special relativity.
Another big departure from classical mechanics is the idea of probabilities. The wave function in the Schrodinger equation is related to the probability of finding the particle in a given location if you were to measure it. Prior to measurement, we cannot know in advance where it will be. So the outcome is not deterministic, but probabilistic. Only the probabilities of the alternative possible outcomes are deterministic.
The world and the universe would be very different if it was not quantized. It would be a deterministic world where, theoretically the future would be predictable. But the world would not exist as we know it because, atoms could not form, quantum particles would not form. There would be no energy and no radiation. Without quantum mechanics, you could still have spacetime because general relativity does not require quantization. But this universe would be filled with nothing.
What Is Electricity?
Science expert Emerald Robinson explains what electricity is and how it was discovered.
New Dark Matter Discovery
New findings on Dark Matter – the most mysterious substance in the universe – suggest that Einstein’s Theory of Relativity “may be wrong”. What could this revelation mean for both the world of science and beyond?