We made it back to the future, but in a parallel universe

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We made it back to the future, but in a parallel universe

9 July 2010

If you’re a dyed-in-the-wool Back to the Future fan I hope you weren’t taken in by the claim that last Monday, 5 July, was “Future Day”. That being the day Marty McFly and Doc Brown arrived in the future when they travelled forward in time during 1989’s Back to the Future Part II.

The arrival of the time travellers from 1985 last Monday may not have been all bad though, had it have happened. In the twenty-five years since the release of Back to the Future, and only five years out from 2015 — the setting for much of Back to the Future Part II — we still have ground to make up in terms of matching some of the advances in technology seen in the movie trilogy.

So far we’re still lagging in the development of:

Flying cars (actually they exist, but are far from in everyday use)
Hoverboards
Time travel

We have however made advances in other areas, with the advent of:

The World Wide Web
Smart phones
High Definition TV (if that’s much of innovation really, considering we’ve had low-def TVs for years)

There’s still another five years to go though, perhaps by then we’ll at least have hoverboards that are able to match what we can do with skateboards today.

Originally published Friday 9 July 2010, with subsequent revisions, updates to lapsed URLs, etc.

You can travel no further back in time than 1955

18 August 2009

The Time Traveler’s Wife is the latest in a long line of time travel themed movies, and according to physicist Dave Goldberg, makes for a more realistic representation of time travel than most of the (fiction) served to date.

But this is interesting, time travel is (theoretically) only possible to points in time where a time machine already exists, according to Goldberg.

In other words, for Marty McFly to travel from 1985 to back to 1955, as he did in Back to the Future, a DeLorean like time machine would already need to have been in existence in 1955…

According to Einstein’s picture of the universe, space and time are curved and very closely related to each other. This means that traveling through time would be much like traveling through a tunnel in space — in which case you’d need both an entrance and an exit. As a time traveler, you can’t visit an era unless there’s already a time machine when you get there — an off-ramp. This helps explain why we’re not visited by time-traveling tourists from our own future. Futuristic humans don’t drop in for dinner because we haven’t yet invented time travel.

Of course the concept of time travel — in the form of the Flux Capacitor — did exist in 1955, it simply hadn’t taken physical form… does that count?

Originally published Tuesday 18 August 2009, with subsequent revisions, updates to lapsed URLs, etc.

The Big Bang might have been big, but it sounded like a hum

31 October 2003

Judging by the amount of press it generates, it seems we just love talking about the Big Bang, the theory that explains the existence of the universe. And why not? We wouldn’t be here now talking about it, if it er, hadn’t have happened. Theoretically speaking that is.

The latest revelations published in New Scientist suggest the Big Bang was more of a deep hum rather than an explosive, booming, bang. Whether it was a bang or a hum though, there’s no doubting its volume, which was certainly loud.

Another news service carrying the same story compared the noise levels as being similar to a jet aeroplane with its engines operating at full power just ten or so metres above your house.

A little like the noise that Concorde used to create perhaps? Theoretically speaking that is .

Originally published Friday 31 October 2003, with subsequent revisions, updates to lapsed URLs, etc.