# How feasible is it to expect a major breakthrough that allows us sci-fi space travel (and related tech)?

After reading hours on here, I stumbled upon alot of answers that rely on some major changes in our understanding of space and time and its tech to allow us control antimatter or some future thrusters.

From this accepted Answer specific, such breakthrough are kind of expected every 100-200 years.

How realistic is this assumption for our (near) future?

Points on why it may not happen:

• such tech-jumps only happened recently and only once/twice (around industrial revolution I guess and our modern computer times)
• the future may be not this rich for a longer peroid of time regarding war/peace and ressources like fuel or rare metals, which would make it harder to focus on such kinds of science or even to develop large-scale tech
• all major parts in physics seem to be solved (what tech could quantum-physics or the god-equation offer in large scale?)
• I am assuming that the "near future" is the 1 hundred years timeframe you mentioned as you never made that explicitly. – JDSweetBeat Apr 8 '15 at 15:41
• Ion drive in some spacecrafts use magnetic field to expel ionized gas (plasmas) to accelerate in space, much rumored microwave drive a type of reactionless propulsion engine convert electricity into photon and use it momentum to move spacecraft all of these innovations replaced chemical rocket. Some nerds even thinking of finding the switch to higgs boson! – user6760 Apr 8 '15 at 16:06
• "Reactionless"? No, I think you mean that a photon rocket does not carry reaction mass in addition to its power source. Note that the Pioneer Anomoly includes thrust due to differential heat loss on different materials, so in a sense it's already been done. :) – JDługosz Apr 8 '15 at 19:14

A major scientific breakthrough can be expected to happen reasonably soon. The thing is though, with virtually all breakthroughs they have not been anything we could expect ahead of time.

The sheer power available in nuclear reactions was inconceivably before Einstein. In fact there was debate about how the sun could have managed to burn for so long as no chemical reaction could provide enough energy for long enough.

The nature of machines that are powered by steam was equally impossible to imagine in a world where water and wind mills were the main sources of mechanical energy.

The people first working on early computers would have no way of comprehending the possibilities of the Internet and the world wide web. I have a mobile phone in my pocket more powerful than any computer in the world 20 years ago, that can browse the internet wirelessly, generate 3d images, and far far more.

So we can expect to see scientific breakthroughs within our lifetime. But if they are true breakthroughs then only a very few people will have seen them coming before they do.

• only a very few people will have seen them coming before they do - and most other people's guesses will have been very, very wrong. But we'll look at those people who do get it right and go "Wow, they were actually right." – Bobson Apr 8 '15 at 21:07

Buni - I think it's less realistic than we like to think and we're prone to best case scenario futurism. In the 50s through the 70's, the image of the future was also like this...in what we now call 'retro-futurism', we get to see images of the working man kissing his stay at home wife and flying off to work in a jet pack...all with an expected arrival date of before the year 2000. It's worth noting that not only was the technology prediction a long ways off, but also completely failed to take into account the social changes and the movement away from the man + housewife + 3 kids and a white picket fence home.

One of the larger error's we make is focusing on the physical technology while neglecting the social and individual changes that come with each leap...with Industrialization came the mass movement of people from rural farms to the city factories, but it also came with a change in the perception of time. The majority of the population lost the farming schedule, working by daylight in the fields according to the season, and replaced that with a manufacturing cycle of adherence to the clock. Every step was reliant on another step being completed and had the next step relying on it to be completed in time. We would build, put it in a warehouse, and continue on. With the transition to the Information age, people are now having to deal with near instant information access and a sharp deviation away from the 9-5 manufacturing style of life...even to the point where 'on-demand' manufacturing is desirable over the 9-5 manufacture and warehousing operations. It's not a simple process and many people are struggling with the shift

If we're not ready, either as individuals or as a society, for the jump to happen, then it's going to be delayed regardless of how available the technology is. In my opinion, the next major shift in society needs to be a rejection of nationalism and an adoption of 'human' as our primary identity and a movement away from things (money) being our primary motivation (which is a natural evolution towards a post-scarcity society). Note that both of these conditions really aren't in a technological domain, but are ultimately required steps for humanity to continue forward. Of course this neglects the individual change...our move to the information age has sped everything up and removed our adherence to the clock that the manufacturing age demanded. An individual now has near instant access to information regardless of time (I can bank on my phone at 2am if I wanted). The world has become a tiny place with anyone no more than a days travel from any point on the globe to another and we get visibly frustrated from a 2 second lag time on a browser. Each step has come with pretty great changes that semi-invalidates the changes the previous step has brought in. When we begin interplanetary colonization and lets say colonize a moon of saturn, how well are we going to deal with going from a tiny world to a vast solar system where communication between two colonies comes with an hour long lag? It's a little bit of a throw back to colonial days where the journey from the old world to the new world was a month long.

My point of this is to say that the rate of technological discovery is not the limiting factor when it comes to the time frames of these leaps. The timeline on this (near) future is constrained more by our slower social and individual evolution than our technological evolution.

As a physicist, I can tell you we have plenty of areas which remain unsolved and mysterious. If we have solved most things, we wouldn't bother with LHC and other scientific endeavors. There is enough about the universe for scientists to spend hundreds, if not thousands of years, performing more research.

As for expecting certain breakthroughs, it is a very tenuous proposal. It makes the fundamental assumption that the rate of past breakthroughs keeps going. There is no guarantee about this. Even similar ideas, such as Moore's Law, have limits. Therefore you need to take such predictions with a figurative grain of salt.

Skepticism about future breakthroughs being said, there are enough potential new technologies for rockets that there is no reason not to expect more experimentation and new rockets. This is especially true in light of the privatization of space travel, with companies like spacex.

Quantum Physics can have large-scale applications; some are more common while others are being developed. See quantum computing for a good example. Quantum Effects can also be seen in large-scale things, such as neutron stars. MRIs and Electron Microscopes work because quantum principles are being taken advantage of. To say that this branch of physics offers no large-scale benefits is simply wrong. It has already benefited you and I on large scales, although you may not have noticed.

Finally, while many "economically minded" people may think that space travel is unprofitable, it is happening. SpaceX and other companies are going to space. Asteroid mining is a potential cash-cow. Martian Metallurgy can yield unexpected new metals or a cheap source of steel.

I would expect future innovations to happen, given all that there is to discover and explore. Anyone nay-saying future innovations is simply ignoring facts. If there is a future ceiling to technology, it will likely not happen in the next one or two hundred years.

Breakthroughs in craftsmanship, not fundimental laws of physics, are what is driving the current space privitization effort. We still use chemical fuel and Newton's Third Law to make a rocket work — don't expect that to change. There is no magic-bean powered carpet in forseeable future. It is improvements in tools and materials handling that is ongoing, and that also allows the creation of better tools as well as final goods, so it has the potential for exponential growth.

Private companies are trying to make space affordable by making vecicles lighter and more cheaply.

The entire launch vehicle and engines are just a tax on top of what you really wanted to orbit. If you could get the weight down to a feather, you still have the weight of the payload and fuel for that weight. So there is a limit.

However, what allows colleges and startups to access space is the microsat. Even when it still costs \$8600 per pound (which comes to$75,000 for a gallon of milk), a useful payload can be built that is only a few pounds.

Look at an Android smartphone: a few ounces for more compuer power than existed onnthe planet during the Space Race, sensors, optics, and communications capability.

Further improvement that could be at the levelmof a breakthrough in commercial availability of orbital experiments (not in physics) would be the development in infrastructure. The microsat is bloated by shielding, more powerful radio, and the need for self-contained power, so it winds up being 10×10×40 cm rather than a smartphone.

A commercial service could offer orbital hosting, where your microsat is placed in a shielded enclosure with a network connection and power, supplied by them. The suite with its heavy shielding does not need to get sent up every time the interesting guts gets replaced! That would reduce costs by an order of magnitude, all, without needing to discover new laws of physics or invent whole new technologies. Its just investment and building on continuing work.

What is happening: smaller stuff. Nanotechnology, spintronics, novel materials, etc.

What is not going to happen, because we know how it works and that there are limits: chemical energy won't be stored any denser than what is already found in high explosives. That is, rocket fuel won't get orders of magnitude more powerful.

(Non-chemical rockets like ion drives are not useful for getting into orbit. Thrust less than 1g is not going to get anywhere.)

So what about replacing launch rockets with something that does not carry the fuel with it? Cannon launchers have limits, and unless you build a many-miles-long railgun it won't help. Getting as much speed as you can while still in the atmosphere means you can save on reaction mass and get oxygen without carrying it all, but how much does that save? It still relies on the compound interest of the rocket equasion and cutting off the bottom saves many times the direct savings. Easy recovery and reuse of the stage (as it's a plane) needs to be weighed against the weight savings of making it disposable!

So what if you wanted to go to the moon in person? Hundreds of pounds with life-support and snacks, comes to millions of dollars.

If you can't get past chemical launch rockets until much later when space industry is already mature, how about making the rocket fuel cheap?

You can't have exotic toxic materials, just as cars are subject to emmission regulation now. The rocket exhaust will need to be eco-friendly, meaning not as powerful as it might be if you could choose the most potent chemicals without constraint.

But lack of rare metals and such will also make it cheap to produce. In a future with advanced chemestry and nanotechnology, potent molecules can be designed and contained safely, using only common life elements. Hey, it could grow on trees. Ultimately, if gathering and arranging the atoms is cheap, you are limited by the amount of energy you are storing. Less power per mass pays penalty exponentially via the rocket equasion, but look at what petrolium is: organic molecules. Or, liquid oxygen and hydrogen: what if that was cheap, other than the cost of energy?

Later, but before the possibility of space elevators, a commercial capability breakthrough will be to source industrial materials off-earth rather than lifting it. We will be importing raw material and manufacured goods, and leaving will be expensive. Since you only need to get to LEO and then all the life-support and living quarters are from space rather than lifted from Earth, my ticket out (a 250 pound man) will be \$251,000 with today's rockets. Earning power will increase, fixed infrastrucure cost will be amortized (don't need to buy the airplane when I fly coach), and cost to produce the fuel will be smaller relative to the total consumption per person of energy. Whether that means affordable as saving up for a few years, or cheap, depends on breakthroughs in our energy economy. Cheap practical fusion? Or just nearly-free solar power?

A lot depends on what exactly you mean by a breakthrough.

Some breakthroughs like the Agricultural revolution and the Industrial revolution are really a matter of social organization. Steam engines and relatively sophisticated machinery like waterwheel powered saws and mills were known as far back as the Roman Empire, but since slave and animal power was very cheap, mechanical engines of various sorts were specialty devices used to do things like "special effects" at temples (a primitive atmosphere engine was described to open doors at temples, for example). The idea of science was considered a hobby for the wealthy, and technology for lower classes (Vulcan, the god of craftsmen, was the only god described as lame, which gives you an idea of how craftsmen were viewed). Even in the 1500's, the Venetians had developed fairly modern government and banking institutions, and even a primitive assembly line system in their Arsenal, but never took the last step.

Other breakthroughs are a result of actually changing the way we understand the universe. The Scientific revolution changed the world from a random place to one of "cause and effect" which could be quantified and reproduced. Newtonian mechanics allowed the mathematical study of things at scales larger and smaller than what was possible before, and Einstein and the various scientists who developed Quantum mechanics have expanded the scale and scope of what can be observed and understood.

Right now, we seem to be in a sort of consolidation period. As mentioned, much of the "breakthroughs" are really refinements on craftsmanship; rockets still rely on fairly basic ideas dating back hundreds of years, and even "smartphones" simply make use of transistor and integrated circuit technology that is highly refined, but based on ideas dating back more than half a century.

Not to say this isn't useful, and on the NextBigFuture blog, there is an idea being promoted of a "mundane" singularity, where the accumulation of simple refinements still leads to a massive leap in wealth and abilities.

Truly fundamental changes are difficult to predict, and do not come on a "schedule". Physical laws are fairly well understood, and any breakthroughs there will be at scales far beyond what ordinary people could expect to access (cosmology or particle physics). Fundamental changes in the way we organize knowledge and understand things may be possible as new technologies like Big Data become well understood and tools to exploit them become common. I would look for some sort of social change on the order of the Agricultural revolution or Industrial revolution to really be the next breakthrough. The interesting question there becomes:

What will be the driver of this change (humans were well aware of how plants worked through the neolithic era, but generally never bothered to cultivate them, and as mentioned, the Romans in the First Century AD had access to primitive engines and the Venetians had many of the institutions but never took the last step). We have lots of new tools ranging from genetic engineering to material science; are any of these going to be the big thing?

What will trigger the change? The tools might have been around for a long time, but the conditions to make the breakthrough possible might not happen for a long time.