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Three time dimensions, one space dimension: Relativity of superluminal observers in 1+3 spacetime

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Credit: Pixabay/CC0 Public Domain

How would our world be viewed by observers moving faster than light in a vacuum? Such a picture would be clearly different from what we encounter every day. “We should expect to see not only phenomena that happen spontaneously, without a deterministic cause, but also particles traveling simultaneously along multiple paths,” argue theorists from universities in Warsaw and Oxford.

Also the very concept of time would be completely transformed—a superluminal world would have to be characterized with three time dimensions and one spatial dimension and it would have to be described in the familiar language of field theory. It turns out that the presence of such superluminal observers does not lead to anything logically inconsistent, moreover, it is quite possible that superluminal objects really exist.

In the early 20th century, Albert Einstein completely redefined the way we perceive time and space. Three-dimensional space gained a fourth dimension—time, and the concepts of time and space, so far separate, began to be treated as a whole. “In the special theory of relativity formulated in 1905 by Albert Einstein, time and space differ only in the sign in some of the equations,” explains prof. Andrzej Dragan, physicist from the Faculty of Physics of the University of Warsaw and Center for Quantum Technologies of the National University of Singapore.

Einstein based his special theory of relativity on two assumptions: Galileo’s principle of relativity and the constancy of the speed of light. As Andrzej Dragan argues, the first principle is crucial, which assumes that in every inertial system the are the same, and all inertial observers are equal. “Typically, this principle applies to observers who are moving relative to each other at speeds less than the speed of light (c). However, there is no fundamental reason why observers moving in relation to the described physical systems with speeds greater than the speed of light should not be subject to it,” argues Dragan.

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What happens when we assume—at least theoretically—that the world could be observable from superluminal frames of reference? There is a chance that this would allow the incorporation of the basic principles of quantum mechanics into the . This revolutionary hypothesis of prof. Andrzej Dragan and prof. Artur Ekert from the University of Oxford presented for the first time in the article “Quantum principle of relativity” published two years ago in the New Journal of Physics.

There they considered the simplified case of both families of observers in a space-time consisting of two dimensions: one spatial and one time dimension. In their latest publication in the journal Classical and Quantum Gravity, titled “Relativity of superluminal observers in 1 + 3 spacetime”, a group of 5 physicists goes a step further, presenting conclusions about the full four-dimensional spacetime.

The authors start from the concept of space-time corresponding to our physical reality: with three spatial dimensions and one time dimension. However, from the point of view of the superluminal observer, only one dimension of this world retains a spatial character, the one along which the can move.

“The other three dimensions are time dimensions,” explains prof. Andrzej Dragan. “From the point of view of such an observer, the particle ‘ages’ independently in each of the three times. But from our perspective—illuminated bread eaters—it looks like a simultaneous movement in all directions of space, i.e. the propagation of a quantum-mechanical spherical wave associated with a particle,” comments prof. Krzysztof Turzyński, co-author of the paper.

It is, as explained by prof. Andrzej Dragan, in accordance with Huygens’ principle formulated in the 18th century, according to which every point reached by a wave becomes the source of a new spherical wave. This principle initially applied only to the light wave, but extended this principle to all other forms of matter.

As the authors of the publication prove, the inclusion of superluminal observers in the description requires the creation of a new definition of velocity and kinematics. “This new definition preserves Einstein’s postulate of constancy of the speed of light in vacuum even for superluminal observers,” prove the authors of the paper. “Therefore, our extended special relativity does not seem like a particularly extravagant idea,” adds Dragan.

How does the description of the world to which we introduce superluminal observers change? After taking into account superluminal solutions, the world becomes nondeterministic, particles—instead of one at a time—begin to move along many trajectories at once, in accordance with the quantum principle of superposition.

“For a superluminal observer, the classical Newtonian point particle ceases to make sense, and the field becomes the only quantity that can be used to describe the physical world,” notes Andrzej Dragan. “Until recently it was generally believed that postulates underlying quantum theory are fundamental and cannot be derived from anything more basic. In this work we showed that the justification of quantum theory using extended relativity, can be naturally generalized to 1 + 3 spacetime and such an extension leads to conclusions postulated by quantum field theory,” write the authors of the publication.

All particles therefore seem to have extraordinary properties in the extended special relativity. Does it work the other way around? Can we detect particles that are normal for superluminal observers, i.e. particles moving relative to us at superluminal speeds?

“It’s not that simple,” says prof. Krzysztof Turzyński. “The mere experimental discovery of a new fundamental particle is a feat worthy of the Nobel Prize and feasible in a large research team using the latest experimental techniques. However, we hope to apply our results to a better understanding of the phenomenon of spontaneous symmetry breaking associated with the mass of the Higgs particle and other particles in the Standard Model, especially in the early universe.”

Andrzej Dragan adds that the crucial ingredient of any spontaneous symmetry breaking mechanism is a tachyonic field. It seems that superluminal phenomena may play a key role in the Higgs mechanism.

More information:
Andrzej Dragan et al, Relativity of superluminal observers in 1+3 spacetime, Classical and Quantum Gravity (2022). DOI: 10.1088/1361-6382/acad60

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University of Warsaw

 

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Three time dimensions, one space dimension: Relativity of superluminal observers in 1+3 spacetime (2022, December 22)
retrieved 22 December 2022
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Future Space Telescopes Could be 100 Meters Across, Constructed in Space, and Then Bent Into a Precise Shape – Universe Today

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It is an exciting time for astronomers and cosmologists. Since the James Webb Space Telescope (JWST), astronomers have been treated to the most vivid and detailed images of the Universe ever taken. Webb‘s powerful infrared imagers, spectrometers, and coronographs will allow for even more in the near future, including everything from surveys of the early Universe to direct imaging studies of exoplanets. Moreover, several next-generation telescopes will become operational in the coming years with 30-meter (~98.5 feet) primary mirrors, adaptive optics, spectrometers, and coronographs.

Even with these impressive instruments, astronomers and cosmologists look forward to an era when even more sophisticated and powerful telescopes are available. For example, Zachary Cordero 
of the Massachusetts Institute of Technology (MIT) recently proposed a telescope with a 100-meter (328-foot) primary mirror that would be autonomously constructed in space and bent into shape by electrostatic actuators. His proposal was one of several concepts selected this year by the NASA Innovative Advanced Concepts (NIAC) program for Phase I development.

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Corder is the Boeing Career Development Professor in Aeronautics and Astronautics at MIT and a member of the Aerospace Materials and Structures Lab (AMSL) and Small Satellite Center. His research integrates his expertise in processing science, mechanics, and design to develop novel materials and structures for emerging aerospace applications. His proposal is the result of a collaboration with Prof. Jeffrey Lang (from MIT’s Electronics and the Microsystems Technology Laboratories) and a team of three students with the AMSL, including Ph.D. student Harsh Girishbhai Bhundiya.

Their proposed telescope addresses a key issue with space telescopes and other large payloads that are packaged for launch and then deployed in orbit. In short, size and surface precision tradeoffs limit the diameter of deployable space telescopes to the 10s of meters. Consider the recently-launched James Webb Space Telescope (JWST), the largest and most powerful telescope ever sent to space. To fit into its payload fairing (atop an Ariane 5 rocket), the telescope was designed so that it could be folded into a more compact form.

This included its primary mirror, secondary mirror, and sunshield, which all unfolded once the space telescope was in orbit. Meanwhile, the primary mirror (the most complex and powerful ever deployed) measures 6.5 meters (21 feet) in diameter. Its successor, the Large UV/Optical/IR Surveyor (LUVOIR), will have a similar folding assembly and a primary mirror measuring 8 to 15 meters (26.5 to 49 feet) in diameter – depending on the selected design (LUVOIR-A or -B). As Bhundiya explained to Universe Today via email:

“Today, most spacecraft antennas are deployed in orbit (e.g., Northrop Grumman’s Astromesh antenna) and have been optimized to achieve high performance and gain. However, they have limitations: 1) They are passive deployable systems. I.e. once you deploy them you cannot adaptively change the shape of the antenna. 2) They become difficult to slew as their size increases. 3) They exhibit a tradeoff between diameter and precision. I.e. their precision decreases as their size increases, which is a challenge for achieving astronomy and sensing applications that require both large diameters and high precision (e.g. JWST).”

While many in-space construction methods have been proposed to overcome these limitations, detailed analyses of their performance for building precision structures (like large-diameter reflectors) are lacking. For the sake of their proposal, Cordero and his colleagues conducted a quantitative, system-level comparison of materials and processes for in-space manufacturing. Ultimately, they determined that this limitation could be overcome using advanced materials and a novel in-space manufacturing method called Bend-Forming.

This technique, invented by researchers at the AMSL and described in a recent paper co-authored by Bhundiya and Cordero, relies on a combination of Computer Numerical Control (CNC) deformation processing and hierarchical high-performance materials. As Harsh explained it:

“Bend-Forming is a process for fabricating 3D wireframe structures from metal wire feedstock. It works by bending a single strand of wire at specific nodes and with specific angles, and adding joints to the nodes to make a stiff structure. So to fabricate a given structure, you convert it into bending instructions which can be implemented on a machine like a CNC wire bender to fabricate it from a single strand of feedstock. The key application of Bend-Forming is to manufacture the support structure for a large antenna on orbit. The process is well-suited for this application because it is low-power, can fabricate structures with high compaction ratios, and has essentially no size limit.”

In contrast to other in-space assembly and manufacturing approaches, Bend-Forming is low-power and is uniquely enabled by the extremely low-temperature environment of space. In addition, this technique enables smart structures that leverage multifunctional materials to achieve new combinations of size, mass, stiffness, and precision. Additionally, the resulting smart structures leverage multifunctional materials to achieve unprecedented combinations of size, mass, stiffness, and precision, breaking the design paradigms that limit conventional truss or tension-aligned space structures.

In addition to their native precision, Large Bend-Formed structures can use their electrostatic actuators to contour a reflector surface with sub-millimeter precision. This, said Harsh, will increase the precision of their fabricated antenna in orbit:

“The method of active control is called electrostatic actuation and uses forces generated by electrostatic attraction to precisely shape a metallic mesh into a curved shape which acts as the antenna reflector. We do this by applying a voltage between the mesh and a ‘command surface’ which consists of the Bend-Formed support structure and deployable electrodes. By adjusting this voltage, we can precisely shape the reflector surface and achieve a high-gain, parabolic antenna.”

An arrangement of 3 exoplanets to explore how the atmospheres can look different based on the chemistry present and incoming flux. Credit: Jack H. Madden used with permission

Harsh and his colleagues deduce that this technique will allow for a deployable mirror measuring more than 100 meters (328 ft) in diameter that could achieve a surface precision of 100 m/m and a specific area of more than 10 m2/kg. This capability would surpass existing microwave radiometry technology and could lead to significant improvements in storm forecasts and an improved understanding of atmospheric processes like the hydrologic cycle. This would have significant implications for Earth Observation and exoplanet studies.

The team recently demonstrated a 1-meter (3.3 ft) prototype of an electrostatically-actuated reflector with a Bend-Formed support structure at the 2023 American Institute of Aeronautics and Astronautics (AIAA) SciTech Conference, which ran from January 23rd to 27th in National Harbor, Maryland. With this Phase I NIAC grant, the team plans to mature the technology with the ultimate aim of creating a microwave radiometry reflector.

Looking ahead, the team plans to investigate how Bend-Forming can be used in geostationary orbit (GEO) to create a microwave radiometry reflector with a 15km (9.3 mi) field of view, a ground resolution of 35km (21.75 mi) and a proposed frequency span of 50 to 56 GHz – the super-high and extremely-high frequent range (SHF/EHF). This will enable the telescope to retrieve temperature profiles from exoplanet atmospheres, a key characteristic allowing astrobiologists to measure habitability.

“Our goal with the NIAC now is to work towards implementing our technology of Bend-Forming and electrostatic actuation in space,” said Harsh. “We envision fabricating 100-m diameter antennas in geostationary orbit with have Bend-Formed support structure and electrostatically-actuated reflector surfaces. These antennas will enable a new generation of spacecraft with increased sensing, communication, and power capabilities.”

Further Reading: NASA

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Amateur N.S. astronomer captures magic of the green comet – CBC.ca

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Nova Scotia·Audio

Tim Doucette with the Deep Sky Eye Observatory in southwestern Nova Scotia has captured a dazzling time-lapse of the green comet that’s making a rare pass near Earth.

Comet C/2022 E3 (ZTF) making its closest approach to Earth on Wednesday

Tim Doucette captured a two-hour time-lapse of the green comet over the weekend. (Tim Doucette/Deep Sky Eye Observatory)

An amateur astronomer from southwestern Nova Scotia has captured a dazzling time-lapse of the green comet that’s making a rare pass near Earth.

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The last time the comet was this close to our planet was 50,000 years ago. Many Canadians are looking up at the stars this week as the comet gets ready to make its closest approach on Wednesday.

Tim Doucette with the Deep Sky Eye Observatory near Yarmouth, N.S., is among them.

He took a two-hour time-lapse of the comet during the early-morning hours of Jan. 28.

“If you’ve got a telescope and you look closely at the comet and the background stars, it’s travelling relative in our sky about one-quarter degrees per hour,” he told CBC Radio’s Mainstreet Halifax. “So within a few minutes you can see that the comet’s actually making motion in the night sky.”

You can listen to Doucette’s full interview with host Jeff Douglas here:

Mainstreet NS8:09Astronomer Tim Doucette captures images of rare green comet

A rare green comet that orbits our sun once every 50,000 years is now in our neighbourhood, and already an amateur astronomer has captured dazzling imagery of it.

Amateur N.S. astronomer captures magic of the green comet

2 hours ago

Duration 0:09

Tim Doucette with the Deep Sky Eye Observatory in southwestern Nova Scotia has captured a dazzling time-lapse of the green comet that’s making a rare pass near Earth.

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With files from CBC Radio’s Mainstreet Halifax

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Kemptville author’s book being sent to the moon

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One of Michael Blouin’s books is going to be launched into space on a microdisk and stay on the surface of the moon. (Submitted by Michael Blouin)

An author from North Grenville, Ont., is going to be part of a small club of authors whose works will be sent to the moon.

Michael Blouin of Kemptville says he’s been interested in space travel since the Apollo 11 mission that landed humans on the moon for the first time.

To be part of a group of hundreds of authors having their work immortalized within the vast expanse of space has him “gobsmacked.”

“I take comfort in the fact that no matter what happens, it looks like my books … will survive and be there,” he said.

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“I sometimes wake up at night and say ‘Oh yeah, I’m going to the moon. Wow.’ It’s kind of amazing.”

How it came to be

Blouin said he’s been a lifelong fan of NASA and space exploration, so when the opportunity to get his work in the Writers on the Moon project came up, he had to take it.

Then around the deadline to apply, his house burned down.

Amid the chaos of not having anywhere to live and then moving into his son’s house, he realized he’d missed his chance.

“I had missed the deadline to apply for this program for books to go to the moon by 12 hours and I was just kicking myself,” he said.

“I lost everything and now I’d missed out on my chance to do something I’d always dreamed about doing.”

Luckily a friend and author in Newfoundland, Carolyn R. Parsons, said she had managed to get some of her work included in the project and had enough space on her microdisk to include him as well.

A rocket sits upright.
This rocket will carry a lander and books from a couple hundred authors up to the moon. (United Launch Alliance)

When do the books go?

The NASA launch is scheduled for Feb. 25 at Cape Canaveral in Florida, which will see his book Skin House brought to the stars along with other works of independent fiction.

Blouin is getting the chance to see the launch.

“These launches sometimes get delayed due to technical reasons or due to weather,” he said.

“But I’m hoping to give myself a big enough window that I’ll actually be on site.”

Blouin had some advice for people who aspire to write or create.

“Any young person aspiring in the arts just shouldn’t give up. Keep trying,” he said. “It can be a tough go but it’s worth every moment.”

He’s getting another of his books — I am Billy the Kid — up to the moon in 2024.

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