Lifeboat Foundation: Safeguarding Humanity
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Einstein’s theory of relativity paved the way for black holes’ discovery, but the concept behind their existence was so bizarre that even the scientific visionary was not convinced.

More than a century ago, Albert Einstein stunned the world when he explained the universe through his theory of general relativity. The theory not only described the relationship between space, time, gravity and matter, it opened the door to the theoretical possibility of a particularly mind-boggling phenomenon that would eventually be called black holes.

The concept that explains black holes was so radical, in fact, that Einstein, himself, had strong misgivings. He concluded in a 1939 paper in the Annals of Mathematics that the idea was “not convincing” and the phenomena did not exist “in the real world.”

The unveiling of the first-ever picture of a black hole by the Event Horizon Telescope in April 2019, however, not only confirmed Einstein’s original theory, but also provided indisputable proof that the gravitational monsters are, in fact, real.

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Solar EV startup Aptera Motors continued its welcomed level of public transparency today, posting another progress update video for February, offering some juicy details. Aptera co-founder Steve Fambro walks you through the first glimpse at the upcoming Aptera app, which promises several cool features; plus, we get a look at some Solar EV battery packs and some hints at how safe the production vehicle will be. You can learn more in the full video below.

There is a multitude of reasons why Aptera Motors is different from the other OEMs out there. The most obvious is that the California-based startup is really the only company left trying to bring Solar EVs to full-scale production, and it is closer than ever, following a successful $34 million crowdfunding program.

Additionally, Aptera constantly keeps its growing fanbase as well as EV enthusiasts in the know of its progress in developing its solar EVs, posting monthly updates to YouTube. There is also plenty of news coming out of Aptera HQ in between those monthly videos. For example, Aptera offered the public a look at its production-intent build process in mid-February.

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Quantum materials have generated considerable interest for computing applications in the past several decades, but non-trivial quantum properties—like superconductivity or magnetic spin—remain in fragile states.

“When designing quantum materials, the game is always a fight against disorder,” said Robert Hovden, an associate professor of materials science and engineering at the University of Michigan.

Heat is the most common form of disorder that disrupts quantum properties. Quantum materials often only exhibit exotic phenomena at very low temperatures when the atom nearly stops vibrating, allowing the surrounding electrons to interact with one another and rearrange themselves in unexpected ways. This is why quantum computers are currently being developed in baths of liquid helium at −269 °C, or around −450 F. That’s just a few degrees above zero Kelvin (−273.15 °C).

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Some of Apple’s biggest investors are set to pressure the company tomorrow to reveal its use of artificial intelligence tools (via the Financial Times).

Apple’s annual shareholder meeting takes place tomorrow, allowing those with a major stake in the company to put forward proposals. One resolution proposed by the American Federation of Labor and Congress of Industrial Organizations (AFL-CIO) asks Apple to disclose its use of AI and any ethical guidelines that the company has adopted regarding the technology.

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Tesla has made significant strides in improving its supply chain sustainability and human rights practices, as per a new study by environmental group Lead the Charge. This was highlighted by the fact that the electric vehicle giant jumped from ninth to third place in the group’s annual Auto Supply Chain Leaderboard and Report.

Lead the Charge’s Auto Supply Chain Leaderboard and Report analyzes publicly available data from 18 of the industry’s leading automotive manufacturers. The study also provides rankings of automakers’ efforts to eliminate emissions, environmental harms, and human rights violations from their supply chains. In a press release, Lead the Charge noted that its study comes at a crucial time as industry experts are calling for automakers to foster a cleaner supply chain.

Tesla is among the automakers that stood out in Lead the Charge’s study. As per the environmental group, Tesla achieved the largest score increase among its peers in the study, with the company jumping from ninth to third place. Tesla was also the only company to make improvements across all eight of the study’s indicator categories.

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Imagine what it must have been like, as it was for so long throughout human history and prehistory, to look up at the wonders of the night sky in ignorance: not knowing what you were seeing or where any of it came from. All you could behold with your eyes were those glittering points of light in the sky: the Moon, the planets, the stars, a few deep-sky objects (or nebulae), and the tapestry of the Milky Way, with no way of knowing what they were made of, where they came from, or what any of it meant.

Today, the story is very different. Nearly all of the night sky objects we can see with our naked eye are objects present within the Milky Way galaxy. A few of those deep-sky objects turn out to be galaxies, with trillions of more galaxies — including small, faint, and ultra-distant ones — observable with superior tools. These galaxies all expand away from one another, with more distant objects expanding at greater speeds than nearer ones.

The expanding Universe swiftly led to the idea of the Big Bang, which was then confirmed and validated. The Big Bang was then modified to include an even earlier stage known as cosmic inflation, which preceded and set up the Big Bang’s initial conditions. That’s the current status of our understanding of the beginning as of today, in early 2024. Here are the biggest questions, both answered and unanswered, that we still have about the earliest phases of our Universe.

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The purpose of this work is to investigate how several inflationary and bouncing scenarios can be realized by imperfect fluids. We shall use two different theoretical frameworks, namely classical cosmology and Loop Quantum Cosmology (LQC) (see where the derivation of the Hamiltonian in LQC was firstly derived to yield the modified Friedman equation, and also see for a recent derivation of the effective Hamiltonian in LQC, which was derived by demanding repulsive gravity, as in Loop Quantum Gravity). In both cases we shall investigate which imperfect fluid can realize various inflationary and bouncing cosmology scenarios. The inflationary cosmology and bouncing cosmology are two alternative scenarios for our Universe evolution. In the case of inflation, the Universe starts from an initial singularity and accelerates at early times, while in the case of the bouncing cosmology, the Universe initially contracts until it reaches a minimum radius, and then it expands again. With regards to inflation, we shall be interested in four different inflationary scenarios, namely the intermediate inflation, the Starobinsky inflation, and two constant-roll inflation scenarios. With regards to bouncing cosmologies, we shall be interested in realizing several well studied bouncing cosmologies, and particularly the matter bounce scenario, the superbounce scenario and the singular bounce.

As we already mentioned we shall use two theoretical frameworks, that of classical cosmology and that of LQC. After presenting the reconstruction methods for realizing the various cosmologies with imperfect fluids, we proceed to the realization of the cosmologies by using the reconstruction methods. In the case of classical cosmology, we will calculate the power spectrum of primordial curvature perturbations, the scalar-to-tensor ratio and the running of the spectral index for all the aforementioned cosmologies, and we compare the results to the recent Planck data. The main outcome of our work is that, although the cosmological scenarios we study in this paper are viable in other modified gravity frameworks, these are not necessarily viable in all the alternative modified gravity descriptions. As we will demonstrate, in some cases the resulting imperfect fluid cosmologies are not compatible at all with the observational data, and in some other cases, there is partial compatibility.

We need to note that the perturbation aspects in LQC are not transparent enough and assume that there are no non-trivial quantum gravitational modifications arising due to presence of inhomogeneities. As it was shown in, a consistent Hamiltonian framework does not allow this assumption to be true. The perturbations issues that may arise in the context of the present work, are possibly more related to some early works in LQC, so any calculation of the primordial power spectrum should be addressed as we commented above.

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