Time Travel

Travelling from 1972 to 1942 or travelling from 2009 to 2042 just like travelling from New York to Washington DC. A lot of street plays and cinemas such as ‘Back to the Future’ have built a lot of plots that revolve around time traveller moving from one time zone to the other. Is it really possible? If yes then, how?

The idea revolves around relative time experience of two travellers one who stays back on the earth and the other who travells inside a space craft at nearly the speed of light. The theory suggests that the time experienced by the traveller would be different from the time experienced by the person on the Earth. So in effect the person who experiences 50 years on the space craft will see that 400 years have elapsed on the surface of the Earth. So in essence he has travelled time or has travelled to the future. (Time dilation)

The assumption that is questionable in this theory is whether aging which is caused by meta physical phenomena will also be influenced by time dilation or whether time itself is more universal as per which a person will age rather than relative time which causes a persons motion into the future.

Atomic clocks have shown to experience time dilation when one is accelerated to near light speed. So can one travel to the past?. Travelling to the past is unlikely as it will affect the principle of causation. This is the famous Grandfather paradox where a traveller when he travels to the past could stop his grandfather from getting married to his grandmother. In this case can he exist now? This is explained by multiple universes, a universe in which he exists now and a universe where he does not exist( where his grandad and grandmom do not get married.)

Even great yogis such as Swami Yogandanda have verified that time travel is possible as some yogis in the past have disappeared as light and reappeared after eons and ages. So what we can see in the future is that technology being developed where a traveller will remain in motion for 10 years and return to the earth after 400 years and our future human civilizations will witness time travel after all!!

Best Travel Tips for First Time Travelers

Traveling opens up your mind to the outer world. The more one travels, more experience one gains and wiser he becomes. However, all this is applicable when one has already traveled quite a bit. Traveling for the first time is definitely a jittery experience for the traveler. There are innumerable things that need to be considered for undertaking a trip and making it successful.

Mentioned below find some extremely useful travel tips for first time travelers so that the trip remains memorable and hassle-free:

Packing

• Keeping travel documents in place – Ensure that you have your passport in place with more than 6 months of validity in place. Arrange for a suitable visa or permit if needed. Book discount business class flights for traveling comfortably and saving money at the same time.

• Pack less – Clothes, shoes, cosmetics should be packed as less as possible. Baggage allowance is restricted. Why pay more money for carrying things you would probably not need? However, make sure to carry good amounts of undergarments as you might not always get a chance of washing them always. Carry band-aids, Imodium and Aspirin.

• Chargers and memory cards – Your electronic devices like mobile, iPad, the tab and even the camera will need charging. Bring respective chargers. Also carry extra memory cards for the camera as you might need it.

• Currency – If you are traveling in your own country, there is no need for currency change. But in case of an international trip, keep some exchanged currency handy.

During travel and transit

• Reach airport early – Airports might not be the best places to hangout, but it is good to be early than being late. Don’t panic during security checks – you are not carrying a bomb with you. Try and have a good meal before the flight as airport prices are exorbitant.

• Relax on the flight – With discount business class seat, relax on the flight. Get an earplug or an eye mask if you want to catch up on some sleep. To remain entertained bring an iPod, a novel, a pack of cards or anything that interests you.

• Setting time as per destination time zone – If the distance is a long one, chances of jet lag are high. Setting time as per destination time zone will help you in getting sleep at the right time so that you feel less jet lagged.

• Cooperate with border officials – This is important. Answer all asked questions truthfully. But do not go overboard with volunteering. Less is more in this regard.

On reaching the destination

• Be polite and courteous – On reaching the new destination, it is always good to be polite and courteous to people you meet. If language is a barrier, ask in signs. Most of the people will help you.

• Avail local transportation while traveling – Hiring a car will not give you the real sense of the place. To get the actual flavor, avail local transportation. With this, you can save money as well as experience the place from close quarters. You can also interact with the commoners via the journey.

• Keep money and valuables in a safe place – At the first place, it is recommended not to carry any kinds of valuables on the trip. However, you will carry some cash for sure. Keep it hidden in some safe place or even better carry it with you. Just don’t keep on checking that to draw public attention.

• Enjoy local foods, drinks and culture – Now that you are on a vacation, you will not get everything like home. Try various kinds of local foods and drinks. Try food stalls that sell authentic and fresh local food. Such foods are fresh and cheaper when compared to foods in big restaurants.

These are some very basic tips for first time travelers. Once you gain the confidence after first time traveling, things will become simpler for you in future!

Time Travel: It’s Been Done Before!

Could we really travel through time? The short answer is yes! That’s right. We all have the ability to leap forward through time, even if we don’t realize it. If you wanted to jump to the future, you can simply go to sleep and wake up a few hours later right? Of course that’s cheating the question. We want to be able to go back and redo those silly mistakes we made many years ago. who doesn’t wish they could go back and talk to their 15-year-old self? Tell them not to make the mistakes you did (or they will). Or perhaps you’d rather travel 500 years into the future and see those flying cars we were promised by the year 2000. Fortunately, time travel is theoretically possible.

In fact there is no law in physics that prevents time travel. That’s right, according to all the laws of physics we know, it’s perfectly plausible to travel through time at will. But as the saying goes, with great power comes great responsibility. Time travel is an extremely dangerous endeavor with devastating consequences, and is also riddled with paradoxes.

For example, what if I travelled back in time and prevented World War II? Sounds like a brilliant idea right? Countless lives would be saved, I’d be hailed as a hero! Not necessarily. Although I’d be saving lives, I’d also be destroying others. What about all the technology that we rely on today that was developed during the war, such as jet engines and nuclear power. In fact the world map could be completely different. We could actually be worse off than simply leaving history as it was.

Another famous time travel paradox is the grandfather paradox, which basically states that if we were to say for instance, I travel back to a time before my parents were born and prevent my grandfather from meeting my grandmother. My parents couldn’t have met and thus, I would never have been born. So how could I have gone back in time to prevent my grandparents from meeting in the first place.

So we can see that time travel could be a bad idea, but let’s say we really want to go back in time, how would we do it? Well first we need to understand how time works.

Time is something we are all very familiar with, we all know what it is, but yet we can’t see it, touch it, we can’t seem to interact with it in any way, we can only observe it. Isaac Newton thought that time was constant and never deviated, which would of course make time travel impossible. Even Einstein believed it was impossible, yet it is his equations that make it possible. Einstein theorized that space and time are inexplicably linked in what he refers to as “space-time”. So in theory, if I was to warp space with something extremely powerful like a black hole, I would also be warping time. While this appears to be true and scientists continue to explore its possibilities, the real possibility for time travel, seems to be in his other theory; Relativity. In fact time travel using relativity isn’t just a theory, it’s actually been done, several times! Now you probably think I’m crazy but the secret seems to be in going extremely fast.

According to Einstein’s theory of general relativity, no object with mass may travel faster than the speed of light, which is an astonishing 299,792,458 metres per second in a vacuum (that’s no air). That’s an incredible 1,080 million kilometres an hour! So according to General Relativity, we can only travel at 99.99% the speed of light. But lets say for instance that I’m sitting at the back of a plane travelling at the speed of light and I walk to the front of the plane from the back at a rate of 10 kilometres an hour. I’ll leave the equations out of this, but that would mean that my speed plus the speed of the plane would mean that I’m travelling at 1,080 million and ten kilometres an hour, which is 10km/h faster than light, right? Wrong. According the theory of relativity, time would actually slow down for me to prevent me from travelling faster than light. Sounds weird doesn’t it.

Of course this scenario would never happen in real life, as I have already said we can’t travel at or faster than the speed of light. In fact you would need more than an infinite supply of fuel to travel faster than light, which is obviously impossible.

So then what is relativity? Einsteins theory of relativity basically states that if I’m driving down the road at 50km/h and drive past someone standing on the side of the road, to them I would appear to be travelling at 50km/h, I’m sure you already know this. However to me in the car, they too would travel past me at 50km/h. But then if someone where to drive beside me in another car travelling at 50km/h, to them I would appear to be completely stationary. Hard to believe? It’s the same thing that makes it look the car driving beside you on the highway sometimes seems to be floating just outside your window. I’ll leave the complicated equations out of this for now, but you can use simple addition and subtraction to confirm this theory. If you’re travelling in the same direction as the object you’re observing, in this case the other car, you subtract your speed from theirs. So 50km/h minus 50km/h is equal to 0km/h. so they would appear to be stationary. If we’re traveling in the opposite direction we add our speed to theirs. So 50km/h plus another 50km/h is equal to 100km/h. So if we drove past the other car at the same speed in the opposite direction, they would appear to be travelling at 100km/h.

So how does all this work, and more importantly, how did they actually manage to travel through time? Well as it turns out, the faster we travel, the slower time will pass. This was proven when scientists placed an atomic clock, which is an extremely accurate clock down to one billionth of a second, on the space shuttle and observed it its behavior. Before launch the clock was perfectly synced with another atomic clock here on earth, and once the shuttle had returned to earth they put the two clocks together. They then discovered the clock from the shuttle was slightly behind the clock that remained on earth. meaning time had past slower for the clock on the shuttle than the clock that remained on Earth.

So basically astronauts are in fact also time travellers. Sergei Krikalev, the current record holder for the longest time spent in space (about 804 days or 2.2 years) is actually half a second behind the rest of the world. furthermore, scientists have actually calculated that if we could orbit the Earth at 99.99% the speed of light for 7 whole years, we would actually land back on earth 500 years in the future. This effect is known as Time Dilation. What a spectacular realisation! Time travel may actually be within our reach after all. The only problem is inventing a machine or vehicle capable of travelling that fast. Unfortunately it looks like that might be just out of our reach for now. We would actually need the power of a whole star to get to that speed.

But what about travelling back in time? So far neither general or special relativity allow for travelling backwards in time and it appears as though no other laws of physics will allow travel to the past. Such travel to the past, as stated above would lead to paradoxes that could result in the collapse of an entire universe, or a completely new one to be formed. This is part of the Many World Interpretation of Quantum Theory. There are other theories to travel both forward and backwards in time such as black holes and wormholes, but I’ll discuss those in the future.

So for now it looks like we could theoretically travel to the future, but unfortunately we can’t go back and tell our younger self not to buy that car from that dodgy looking salesman, or to buy stocks in Apple and Microsoft when they first start out. So we’ll just have to settle for travelling forwards in time at the same rate we always have, and just to wait to see what the future holds.

Time Travel Into the Past

We know that time travel into the future is possible. Stephen Hawking says, “We do not have the technology today to do this, but it is just a matter of engineering; we know it can be done.” In Time Travel in Einstein’s Universe: The Physical Possibilities of travel Through Time, physicist J. Richard Gott says “if we can accelerate protons to greater than 99.995 percent of the speed of light, we could also send off an astronaut at the same speed. It’s just a matter of cost.”

The idea of time travel into the past is a far more exciting prospect though. Who hasn’t wanted to travel back into the past? Some would like to return to the past permanently to live in a simpler time and escape forever the stress, crime, pollution, and other unpleasant aspects of 21st century living. Some would like to be time tourists and actually be present in the crowd to hear the Gettysburg Address delivered by President Lincoln himself, to watch the pyramids being built, or to witness firsthand any number of historical events. Some would like to go back to do or undo things that affected their own lives.

There was a young lady called Bright
Who could travel far faster than light;
She set off one day,
In a relative way,
And returned home the previous night.
A.H. R. Buller

A cute limerick, but is it possible? Yes, says, Stephen Hawking, if one can travel faster than the speed of light, one can travel back in time in the same manner that one can travel into the future-by riding a really fast spaceship. The problem, he says, is that while we can accelerate particles to 99.99 percent of the speed of light, we have as yet been unable to exceed the speed of light. Nevertheless, Hawking says, travel to the past may be possible through the use of wormholes. The idea of wormholes is not new. In 1935, Einstein and Rosen wrote a paper saying that the Theory of Relativity allowed for the existence of wormholes and much has been written about them since, but as yet we have no conclusive evidence that they actually exist.

Some scientists theorize that time travel into the past may be possible through the use of cosmic strings, which are thin strands of high-density material left over from the early universe. Like wormholes, we don’t know if cosmic strings exist, but Gott says, “If cosmic strings exist, you could travel in a spaceship [at 99.9999999999 percent of the speed of light] and outrun a light beam by taking the shorter of two paths around a cosmic string. The door to time travel to the past begins to crack open.”

Doubts that travel into the past might become possible in the future are rooted not so much in terms of physics and technology, but in terms of intuition and what are perceived to be the use of logic or common sense. For example, if a man were to travel back in time and kill his grandfather before his grandfather ever had any children, then he never would have existed himself and therefore could have never traveled back into time. Furthermore, if time travel to the past becomes a reality at some point in the future, why has there never been any record of people from the future showing up in all of recorded history?

There are many similar questions and many possible answers, some simple and some very complicated. Many people are convinced that time travelers from the future have made trips into the past. There are two types of evidence. The first is artifacts left behind by time travelers. One example is a watch/ring found in December 2008 in a Chinese tomb that had been sealed for 400 years. The second type of evidence is photographs in which there are people who appear to be from another era. An example is the unknown woman in the 1928 Charlie Chaplin movie, “The Circus.” She is walking along in a background shot speaking into what appears to be a communications device. She is alone, and appears to be carrying on a conversation. These and similar examples can be found on the internet as well the opinions of people seeking to debunk the evidence. Who knows?

The only thing certain about time travel into the past is that people will always dream of it and always be fascinated by it.