One of the biggest problem with creating an actual transporter is data, too much of it. I have heard a lot of stories about how much data it would take to send a human flying from one end of the world to another is miliseconds. Anything from hard drives stacked from here to the moon up to hard drives stacked from here to the centre of the galaxy (I’m guessing the latter was quite a while back). In order to send the data anywhere fast you’d need a data stream of over a metre wide. Not much in our world, gigantic in data streaming terms.
Luckily we can decrease this stream in a number of ways. First you could use smaller wavelengths of the electromagnetic spectrum (e.g. use X-rays instead of ultraviolet light). trouble is that small wavelengths do not travel through optic fibres, you’d need dedicated satellites to send the data to another transporter. Also small wavelengths of the electromagnetic spectrum damage living tissue so you wouldn’t want planes flying trough it for instance.
Instead of going to smaller wavelengths you could also increase the carrying capacity of optic fibres. A new technology promising to do this is a technology that twist the beam of light into a vortex this enables you to send more signals at once through the cable. This allows for a speed currently clocked at 2,5 terabits per second (your internet connection is measured in megabits per second, which is a million times less then terabits). It’s so fast you could stream an entire blue-ray film in a fraction of a second. Actually you could stream about 7 in that second.
There is, however, another way to decrease the data you need to send. Just send less. When physicists talk about a transporter they want to send information about every atom in your body to the other side of the world so you get an exact copy of yourself where you want to go. It would however be smarter to only send the most important information and let the computer extrapolate the rest. We’d want our brains to be scanned very precisely because the connections brain cells make are vital to make you who you are. other parts are less important (e.g. the exact place of a certain blood cell in the body which changes constantly.)
When we start looking at the biochemistry in cells we see that we all share a lot of molecules among all humans. From the relative position of molecules we can even deduce their current state (active or not). So instead of transmitting that you have a protein containing iron 4 nitrogen atoms carbon atoms etc. and their relative place you just transmit haemoglobin whether it is carrying oxygen and it’s orientation in the cell. The computer on the other end will just make a haemoglobin molecule, a huge saving in data. Especially if you consider that we are full of standard proteins. Even if they aren’t it isn’t a problem. A more basic building block of the protein is the amino acid. So you can just send the amino acid sequence and orientation, still a time saver. Same goes for DNA which basically can be described by four letters A T G C a string of these letters is basically enough for a computer to know how to sequence the entire DNA in your body. orientation and nearby proteins give an indication if the DNA is being copied, at rest or curled up ready for cell division.
If we would send data in this manner we could save a lot of bandwidth making it possible to actually transfer the data to another transporter in a second and without a metre wide beam. Downside would be that on a cellular level you wouldn’t be exactly the same. Some proteins might be in a slightly different place then in your original body but you wouldn’t know the difference or be able to tell the difference without an immediate scan on a molecular level.
It might sound crazy to do this. It is however a trick we have learned from our own brain. A brain, when compared to a computer, is extremely energy efficient (it burns about 25W/h) and yet has functions no computer can replicate (conscience for instance). It does this by hard-wiring basic assumptions into our brain. We are, for instance very adept at recognizing faces. So adept even that we recognize two symbols, :), as a smiling face. We are even so good at recognizing faces that we can’t even see what side of a mask is the front and what side the back. By using this and many more short cuts the brain can use it’s relatively limited resources more effectively, devote more resources to more pressing matters.
It could even be a breakthrough in medicine. Missing an arm? just deduce how it should look from the DNA and the bodies proportions and you’re ready to go. Rare genetic disease? Filter out faulty genes and proteins and replace them with good ones. Got HIV? Just filter out the Virus’s RNA. It could even be used to prevent ageing! Every ER might be equipped with a transporter to fix any medical emergency you sustain. There might not even be anything beyond the ER.