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“I view string theory as the most promising way to quantize matter and gravity in a unified way. We need both quantum gravity and we need unification and a quantization of gravity. One of the reasons why string theory is promising is that there are no singularities associated with those singularities are the same type that they offer point particles.” — Robert Brandenberger.
In this thought-provoking conversation, my grad school mentor, Robert Brandenberger shares his unique perspective on various cosmological concepts. He challenges the notion of the fundamental nature of the Planck length, questioning its significance and delving into intriguing debates surrounding its importance in our understanding of the universe. He also addresses some eyebrow-raising claims made by Elon Musk about the limitations imposed by the Planck scale on the number of digits of pi.
Continue reading “Unseen Fluctuations: Challenging Inflation | Robert Brandenberger” »
There is a lot of speculation about the end of the universe. Humans love a good ending after all. We know that the universe started with the Big Bang and it has been going for almost 14 billion years. But how the curtain call of the cosmos occurs is not certain yet. There are, of course, hypothetical scenarios: the universe might continue to expand and cool down until it reaches absolute zero, or it might collapse back onto itself in the so-called Big Crunch. Among the alternatives to these two leading theories is “vacuum decay”, and it is spectacular – in an end-of-everything kind of way.
While the heat death hypothesis has the end slowly coming and the Big Crunch sees a reversal of the universe’s expansion at some point in the future, the vacuum decay requires that one spot of the universe suddenly transforms into something else. And that would be very bad news.
There is a field that spreads across the universe called the Higgs field. Interaction between this field and particles is what gives the particles mass. A quantum field is said to be in its vacuum state if it can’t lose any energy but we do not know if that’s true for the Higgs field, so it’s possible that the field is in a false vacuum at some point in the future. Picture the energy like a mountain. The lowest possible energy is a valley but as the field rolled down the slopes it might have encountered a small valley on the side of that mountain and got stuck there.
Whether you find yourself laying awake at night crippled with anxiety regarding the embarrassing errors of your past, or just love Christopher Nolan’s non-linear storytelling, you may be shocked to learn about the latest scientific discovery. According to a recent write-up from Science Alert, time travel may actually be achievable, using the powerful time dilation of interstellar wormholes.
The Belle II cooperation project at the Japanese research center KEK is helping researchers from all over the world to hunt for new phenomena in particle physics. The international experiment has now reached a major milestone after a team successfully installed a new pixel detector in its final location in Japan.
The size of a soda can, the detector was developed in order to make out the signals coming from certain types of particle decays, that can shed light on the origin of the matter–antimatter asymmetry that has been observed in the universe. The installation ran without a hitch and is a key milestone in the evolution of the experiment and German–Japanese research collaboration.
Based at the SuperKEKB accelerator in Japan’s KEK research center, Belle II is an international collaborative project involving researchers from all over the world. The experiment aims to find answers to the many unresolved questions about the universe that are out there. To this end, the 1,200 or so members of the international Belle II collaboration are searching for signs of new phenomena in physics and unknown particles not covered by the established Standard Model of particle physics.
In a new study, scientists say that a particle that links to a fifth dimension can explain dark matter. (The previous article has been updated.)
Detecting the permanent imprints left by colliding black holes would reveal a universe saturated with infinite symmetries – and narrow the possibilities for a theory of quantum gravity.
Quantum entanglement is one of the most intriguing and perplexing phenomena in quantum physics. It allows physicists to create connections between particles that seem to violate our understanding of space and time.
This video discusses what quantum entanglement really is, and the experiments that help us understand it. The results of these experiments have applications in new technologies that will forever change our world.
Continue reading “Quantum 101 Episode 5: Quantum Entanglement Explained” »
Inside of a black hole, the two theoretical pillars of 20th-century physics appear to clash. Now a group of young physicists think they have resolved the conflict by appealing to the central pillar of the new century — the physics of quantum information.
