Re: What fundamental barriers must be overcome to make spacetime travel a realit

Depends on what exactly you mean by space-time travel, i'll assume that you meant travel through both time and space by folding space-time.

 Space travel by folding or warping space has mathematically already been worked out by physicist Miguel Alcubierre. It involves creating a warp bubble that shrinks space ahead of the ship and expands space behind the ship, much like in star trek. Traveling through time would simply be a extension of this method into the fourth dimension.

However, the energy requirement would be huge, far greater than we could potentially produce with even nuclear power, also it would also require a singularity powerful enough to bend space to the degree we need it to. Currently we are limited to just barely being able to create subatomic singularities that exist only for milliseconds at a time.

In short you need

a colossal power source (antimatter, wich we could theoretically make with modern tech)

a way to make a controled and powerful singularity (again we can theoretically make this with modern tech)

exotic matter particularly matter with a negative mass would make creating the bubble much easier, but we havent found any yet.

So if you have $300 trillian burning a hole in your pocket, you could hire the companies to start making on and have it within a decade or two, there really are no barriers in terms of available technology, you just have to wait for the technology to become affordable. 

LinkedIn meets Tinder in this mindful networking app

Swipe right to make the connections that could change your career.

Getty Images
Swipe right. Match. Meet over coffee or set up a call.

No, we aren't talking about Tinder. Introducing Shapr, a free app that helps people with synergistic professional goals and skill sets easily meet and collaborate.

Keep reading Show less

Space toilets: How astronauts boldly go where few have gone before

A NASA astronomer explains how astronauts dispose of their, uh, dark matter.

  • When nature calls in micro-gravity, astronauts must answer. Space agencies have developed suction-based toilets – with a camera built in to ensure all the waste is contained before "flushing".
  • Yes, there have been floaters in space. The early days of space exploration were a learning curve!
  • Amazingly, you don't need gravity to digest food. Peristalsis, the process by which your throat and intestines squeeze themselves, actually moves food and water through your digestive system without gravity at all.
Keep reading Show less

A world map of Virgin Mary apparitions

She met mere mortals with and without the Vatican's approval.

Strange Maps
  • For centuries, the Virgin Mary has appeared to the faithful, requesting devotion and promising comfort.
  • These maps show the geography of Marian apparitions – the handful approved by the Vatican, and many others.
  • Historically, Europe is where most apparitions have been reported, but the U.S. is pretty fertile ground too.
Keep reading Show less

Can the keto diet help treat depression? Here’s what the science says so far

A growing body of research shows promising signs that the keto diet might be able to improve mental health.

Photo: Public Domain
Mind & Brain
  • The keto diet is known to be an effective tool for weight loss, however its effects on mental health remain largely unclear.
  • Recent studies suggests that the keto diet might be an effective tool for treating depression, and clearing up so-called "brain fog," though scientists caution more research is necessary before it can be recommended as a treatment.
  • Any experiments with the keto diet are best done in conjunction with a doctor, considering some people face problems when transitioning to the low-carb diet.
Keep reading Show less