Lifeboat Foundation

Over ten years ago, the Dark Energy Survey (DES) began mapping the universe to find evidence that could help us understand the nature of the mysterious phenomenon known as dark energy. I’m one of more than 100 contributing scientists that have helped produce the final DES measurement, which has just been released at the 243rd American Astronomical Society meeting in New Orleans.

Dark energy is estimated to make up nearly 70% of the observable universe, yet we still don’t understand what it is. While its nature remains mysterious, the impact of dark energy is felt on grand scales. Its primary effect is to drive the accelerating expansion of the universe.

The announcement in New Orleans may take us closer to a better understanding of this form of energy. Among other things, it gives us the opportunity to test our observations against an idea called the cosmological constant that was introduced by Albert Einstein in 1917 as a way of counteracting the effects of gravity in his equations to achieve a universe that was neither expanding nor contracting. Einstein later removed it from his calculations.

Quantum engineering, a dynamic discipline bridging the fundamentals of quantum mechanics and established engineering fields has developed significantly in the past few decades. Two-level systems such as superconducting quantum bits are the building blocks of quantum circuits. Qubits of this type are currently the most researched and used in quantum computing applications^1,2,3,4,5. The characteristics of the superconducting qubits such as eigen energies, non-linearity, coupling strengths etc. can be tailored easily by adjusting the design parameters^6,7. Qubits have large non-linearity, which makes it possible to selectively address and control them^1,3,7,8. This dynamic property makes superconducting qubits a strong candidate for plethora of applications. Other two-level microscopic quantum systems^{9,10,11,12,13,14} also have certain advantages and may be used in the future.

Quantum devices operate at low temperatures and require good isolation from external noises. Microwave devices, such as circulators and isolators, protect quantum circuits by unidirectionally routing the output signal, whilst simultaneously isolating noise from the output channel back to the quantum circuit. Their non-reciprocal character relies on the properties of ferrites^15,16,17. Ferrite-based non-reciprocal devices are bulky^15,16,17, and they cannot be positioned near the quantum circuit because they require strong magnetic fields. Although commercial ferrite based non-reciprocal devices harness high isolation and low insertion loss, their dependency on magnetic components limits the scalability of cryogenic quantum circuits^15,16,18,19. Various ferrite-free approaches based on non-linear behavior of artificial atoms¹⁶, dc superconducting quantum interference devices (dc-SQUID)^20,21, and arrays of Josephson junctions (JJ’s)^19,22,23,24, have been experimentally demonstrated and implemented. Recently, a circuit based on semiconductor mixers has been used to realize a compact microwave isolator, which the authors claim could be extended to an on-chip device using Josephson mixers, although the “on-chip” demonstration is not yet reported²⁵. Additionally, mesoscopic circulators exploiting the quantum Hall effect to break time-reversal symmetry of electrical transport in 2D systems are explored at a cost of larger magnetic fields deleterious to superconducting circuits^{18,26,27,28,29}. More recently, a passive on-chip circulator based on three Josephson elements operating in charge-sensitive regime was demonstrated³⁰. Such devices are frequently limited by their parameter regime, leaving them charge sensitive and therefore difficult to implement in a practical scenario. However, it is possible to mitigate the charge-sensitivity by carefully tuning the device parameters. Our device operates in a parameter regime that is not sensitive to charge fluctuations or charge parity switching, a fundamental requirement for any practical implementation, and requires small magnetic field. The reported device is a proof of concept (PoC), potentially useful in the applications relevant to microwave read-out components in the field of superconducting quantum circuits.

In this work, we present a robust and simple on-chip microwave diode demonstrating transmission rectification based on a superconducting flux qubit⁸. The concept of the device is shown in Fig. 1a. The flux qubit is inductively coupled to two superconducting resonators of different lengths with different coupling strengths. The design details are reported later in this section. Probing the qubit at the half-flux (degeneracy point) with one tone-spectroscopy, we observe identical patterns of transmission coefficient for signals propagating in the opposite directions, which are shifted by 5 dB in power. This shift indicates the non-reciprocal behaviour in our device, expressed in terms of transmission rectification ratio ® in this article. The origin of this effect is the non-linearity of the flux qubit, which controls the transmission coefficient of the whole structure.

Natasha and Max also appear in a recent video titled “Transhumanism. What it is not” in conversation with David Wood and two representatives of the anti-transhumanist camp, Alexander Thomas and Émile Torres. I’m not familiar with the work of Thomas. I’m more familiar with the work of Torres. I very strongly disagree with most of what Torres says, but I must concede that Torres seems an intelligent and perceptive person, not without a certain endearing grace. However, BS is BS.

I’ve watched and listened again to the awesome conversation between Lex Fridman and Guillaume Verdon aka Beff Jezos, the founder of the movement called effective accelerationism (e/acc) and the company Extropic AI. This long conversation (almost 3 hours) touches a lot of things including physics, quantum, thermodynamics, Artificial Intelligence, LLMs, space, e/acc philosophy & metaphysics, and of course the meaning of life & all that. This is the most complete talk on e/acc so far and is likely to remain so for some time. Watch it all, and let’s accelerate the fuck away from mediocrity toward unlimited extropian and cosmist greatness.

Continue reading “Old and new futurisms in Silicon Valley” »

Researchers at Columbia University have successfully synthesized the first 2D heavy fermion material. They introduce the new material, a layered intermetallic crystal composed of cerium, silicon, and iodine (CeSiI), in a research article published in Nature.

Heavy fermion compounds are a class of materials with electrons that are up to 1,000 times heavier than usual. In these materials, electrons get tangled up with magnetic spins that slow them down and increase their effective mass. Such interactions are thought to play important roles in a number of enigmatic quantum phenomena, including superconductivity, the movement of electrical current with zero resistance.

Researchers have been exploring heavy fermions for decades, but in the form of bulky, 3D crystals. The new material synthesized by Ph.D. student Victoria Posey in the lab of Columbia chemist Xavier Roy will allow researchers to drop a dimension.

Silicon carbide is becoming a major player on the quantum scene. Widely used in specialized electronics goods such as LEDs and electric vehicles, silicon carbide boasts versatility, wide commercial availability, and growing use in high-power electronics, making it an attractive material for quantum information science, whose impact is expected to be profound.

Drawing on physics at the atomic scale, technologies such as quantum computers, networks, and sensors will likely revolutionize areas as varied as communication, drug development, and logistics in the coming decades.

Now, scientists at the U.S. Department of Energy’s (DOE) Argonne National Laboratory, DOE’s Sandia National Laboratories, and partner institutions have conducted a comprehensive study on the creation of qubits—the fundamental units of quantum information processing—in silicon carbide.

When Mickael Perrin started out on his scientific career 12 years ago, he had no way of knowing he was conducting research in an area that would be attracting wide public interest only a few years later: Quantum electronics. “At the time, physicists were just starting to talk about the potential of quantum technologies and quantum computers,” he recalls.

“Today there are dozens of start-ups in this area, and governments and companies are investing billions in developing the technology further. We are now seeing the first applications in computer science, cryptography, communications and sensors.” Perrin’s research is opening up another field of application: Electricity production using quantum effects with almost zero energy loss. To achieve this, the 36-year-old scientist combines two usually separate disciplines of physics: thermodynamics and quantum mechanics.

In the past year, the quality of Perrin’s research and its potential for future applications has brought him two awards. He received not only one of the ERC Starting Grants that are so highly sought-after by young researchers, but also an Eccellenza Professorial Fellowship of the Swiss National Science Foundation (SNS)F. He now leads a research group of nine at Empa as well as being an Assistant Professor of Quantum Electronics at ETH Zurich.

We study the competing effects of collective generalized measurements and interaction-induced scrambling in the dynamics of an ensemble of spin-1/2 particles at the level of quantum trajectories. This setup can be considered as analogous to the one leading to measurement-induced transitions in quantum circuits. We show that the interplay between collective unitary dynamics and measurements leads to three regimes of the average Quantum Fisher Information (QFI), which is a witness of multipartite entanglement, as a function of the monitoring strength. While both weak and strong measurements lead to extensive QFI density (i.e., individual quantum trajectories yield states displaying Heisenberg scaling), an intermediate regime of classical-like states emerges for all system sizes where the measurement effectively competes with the scrambling dynamics and precludes the development of quantum correlations, leading to sub-Heisenberg-limited states. We characterize these regimes and the crossovers between them using numerical and analytical tools, and discuss the connections between our findings, entanglement phases in monitored many-body systems, and the quantum-to-classical transition.

While interactions within a many-body quantum system tend to generate highly correlated states, performing local measurements will typically tend to disentangle the different subsystems. When combined, the interplay between these two effects often lead to measurement-induced transitions, which separate two distinct stable phases: one interaction-driven, where entanglement is high, and another measurement-driven, where entanglement is low. However, different types of measurements can lead to other scenarios, and often also generate entanglement themselves. In this work we study quantum many-body systems where both interactions and measurements take place collectively and thus generate a high degree of entanglement if acting separately. We show that nontrivial competition between these two actors emerges, leading to configurations with very low entanglement.

In a recent study, a team of researchers at Max Planck Institute for Physics proposed that advanced extraterrestrial civilizations may be using black holes as quantum computers. No matter how advanced a civilization may be, we are all bound by the laws of quantum physics and gravity. So, if aliens are indeed out there, they could be using the geometry of spacetime around a black hole which behaves like a quantum computer. And, as if that weren’t enough, quantum computing is also immune to decryption, making it the perfect tool for secure communication. Roger Penrose, famously proposed that it is possible to extract limitless energy from a black hole by tapping into its Ergosphere. This is a region just outside the event horizon, where matter falling into the black hole forms a disk that spins at nearly the speed of light and emits massive amounts of radiation. Several researchers now suggest that this may be the ultimate power source for advanced civilizations. Subscribe to Science Time: https://www.youtube.com/sciencetime24 #science #shorts #space

Cosmologists believe that multiple universes really exist; they call the whole vast collection, which might even be infinite in number, the ‘multiverse’. But how are all these universes generated? There are several ways, each radically different from the others, each incredibly fascinating, each capable of generating infinite universes.

Free access to Closer to Truth’s library of 5,000 videos: http://bit.ly/376lkKN

Continue reading “Lee Smolin — How are Multiple Universes Generated?” »