Space

The Idea Of Using Warp Drive To Travel Across Entire Universe

Published

2 years ago

April 27, 2021

Could warp drive actually become a reality? The idea of using warp drive to travel across large distances is not as far-fetched as it might seem. Physicist Mario Borunda from Oklahoma State University investigates.

The closest star to Earth is Proxima Centauri. It is about 4.25 light-years away, or about 25 trillion miles (40 trillion km). The fastest ever spacecraft, the now- in-space Parker Solar Probe will reach a top speed of 450,000 mph. It would take just 20 seconds to go from Los Angeles to New York City at that speed, but it would take the solar probe about 6,633 years to reach Earth’s nearest neighboring solar system.

If humanity ever wants to travel easily between stars, people will need to go faster than light. But so far, faster-than-light travel is possible only in science fiction.

In Issac Asimov’s Foundation series, humanity can travel from planet to planet, star to star or across the universe using jump drives. As a kid, I read as many of those stories as I could get my hands on. I am now a theoretical physicist and study nanotechnology, but I am still fascinated by the ways humanity could one day travel in space.

Some characters – like the astronauts in the movies “Interstellar” and “Thor” – use wormholes to travel between solar systems in seconds. Another approach – familiar to “Star Trek” fans – is warp drive technology. Warp drives are theoretically possible if still far-fetched technology. Two recent papers made headlines in March when researchers claimed to have overcome one of the many challenges that stand between the theory of warp drives and reality.

But how do these theoretical warp drives really work? And will humans be making the jump to warp speed anytime soon?

Compression and expansion

Physicists’ current understanding of spacetime comes from Albert Einstein’s theory of General Relativity. General Relativity states that space and time are fused and that nothing can travel faster than the speed of light. General relativity also describes how mass and energy warp spacetime – hefty objects like stars and black holes curve spacetime around them.

This curvature is what you feel as gravity and why many spacefaring heroes worry about “getting stuck in” or “falling into” a gravity well. Early science fiction writers John Campbell and Asimov saw this warping as a way to skirt the speed limit.

What if a starship could compress space in front of it while expanding spacetime behind it? “Star Trek” took this idea and named it the warp drive.

In 1994, Miguel Alcubierre, a Mexican theoretical physicist, showed that compressing spacetime in front of the spaceship while expanding it behind was mathematically possible within the laws of General Relativity. So, what does that mean?

Imagine the distance between two points is 10 meters (33 feet). If you are standing at point A and can travel one meter per second, it would take 10 seconds to get to point B. However, let’s say you could somehow compress the space between you and point B so that the interval is now just one meter.

Then, moving through spacetime at your maximum speed of one meter per second, you would be able to reach point B in about one second. In theory, this approach does not contradict the laws of relativity since you are not moving faster than light in the space around you. Alcubierre showed that the warp drive from “Star Trek” was in fact theoretically possible.

Proxima Centauri here we come, right? Unfortunately, Alcubierre’s method of compressing spacetime had one problem: it requires negative energy or negative mass.

A negative energy problem

Alcubierre’s warp drive would work by creating a bubble of flat spacetime around the spaceship and curving spacetime around that bubble to reduce distances. The warp drive would require either negative mass – a theorized type of matter – or a ring of negative energy density to work. Physicists have never observed negative mass, so that leaves negative energy as the only option.

To create negative energy, a warp drive would use a huge amount of mass to create an imbalance between particles and antiparticles.

For example, if an electron and an antielectron appear near the warp drive, one of the particles would get trapped by the mass and this results in an imbalance. This imbalance results in negative energy density. Alcubierre’s warp drive would use this negative energy to create the spacetime bubble.

But for a warp drive to generate enough negative energy, you would need a lot of matter. Alcubierre estimated that a warp drive with a 100-meter bubble would require the mass of the entire visible universe.

In 1999, physicist Chris Van Den Broeck showed that expanding the volume inside the bubble but keeping the surface area constant would reduce the energy requirements significantly, to just about the mass of the sun. A significant improvement, but still far beyond all practical possibilities.

A sci-fi future?

Two recent papers – one by Alexey Bobrick and Gianni Martire and another by Erik Lentz – provide solutions that seem to bring warp drives closer to reality.

Bobrick and Martire realized that by modifying spacetime within the bubble in a certain way, they could remove the need to use negative energy. This solution, though, does not produce a warp drive that can go faster than light.

Independently, Lentz also proposed a solution that does not require negative energy. He used a different geometric approach to solve the equations of General Relativity, and by doing so, he found that a warp drive wouldn’t need to use negative energy. Lentz’s solution would allow the bubble to travel faster than the speed of light.

It is essential to point out that these exciting developments are mathematical models. As a physicist, I won’t fully trust models until we have experimental proof. Yet, the science of warp drives is coming into view. As a science fiction fan, I welcome all this innovative thinking. In the words of Captain Picard, things are only impossible until they are not.

Mario Borunda, Associate Professor of Physics, Oklahoma State University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Space

Earth-like world covered by raging volcanoes found in space

Published

2 days ago

May 28, 2023

Scientists at the University of California have discovered a planet
that may bear a resemblance to Earth. However, unlike our planet, this
peaceful planet is covered with fierce volcanoes. News of the discovery
was published in the journal Nature.

The new planet was discovered using the Kepler telescope, which
explores outer space in search of exoplanets. According to scientists,
the planet is in the life zone of its star and may have conditions for
the development of life.

However, the presence of volcanoes on the surface of this planet may
mean that it is not suitable for life. This is due to the fact that
volcanoes can emit gases into the atmosphere, which can be poisonous to
living organisms.

On the other hand, scientists believe that the presence of volcanoes
on this planet may mean there is a magnetic field that protects it from
harmful cosmic rays. This may be one of the factors contributing to the
development of life on this planet.

Although the planet is 110 light years away from Earth, scientists
hope that it could be the subject of future research. However, this will
require new telescopes and more accurate measurement methods.

Interestingly, the search for exoplanets is one of the hottest topics
in modern astronomy. Scientists around the world are looking for
planets that may have conditions for the development of life. Some of
these planets are only a few light years away from Earth.

In addition, there is a theory that life on Earth may have originated
through volcanic activity. Volcanoes may have created the conditions
for the formation of the first organic compounds, which then led to the
emergence of life.

Space

Asteroid 1994 XD: Threat to Earth or opportunity for space exploration?

Published

2 days ago

May 28, 2023

On June 12, 2023, the asteroid 1994 XD, which is over 500 meters in
diameter, will approach Earth. Despite the fact that it will be 3.1
million kilometers away, which is 8 times the average distance to the
Moon, many are asking – can this asteroid become a threat to our planet?

It is worth noting that asteroids, like comets, pose a threat to the
Earth, but the probability of collision with them is very low. In
addition, there are many programs and projects to track space bodies,
which allow you to identify a potential threat in time and take measures
to prevent it.

However, asteroids are also of interest to scientists and space
research. Studying the composition and structure of these bodies can
help scientists better understand the origin of the solar system and the
possibilities for life in space.

For example, asteroids may contain water and other elements necessary
for life, which could be used to build space stations and bases on
other planets. In addition, studying asteroids can help scientists
develop methods to defend against potential threats from space.

The asteroid 1994 XD was discovered in 1994 by the Kitt Peak
Observatory and has not posed a threat to Earth since then. Its close
approach to our planet will be an opportunity to study this cosmic body
in more detail and expand our knowledge of space.