[ScientificSorcerer (OP)]

Rockets have always been what we humans have used to get into space BUT traditional rockets are rather expensive and wasteful. Personally I believe a new form of space craft needs to be imagined because what we have today simply wont take us to other stars practically and cheaply.

So I ask you if you can imagine radical new space propellants and technologies, as if you were trying to make a REAL star trek/wars worthy vessel. Just for fun.

I have come up with an unusual theoretical model maybe you could build on it or come up with something entirely different.

to begin I believe a very powerful propellant is needed, one that will be as light as possible yet pack the most thrust.  I have heard plasma rockets are the most fuel efficient types of rockets but non have been developed as a take off thruster.  I wonder if it's possible to make plasma thrusters powerful enough to be used as a means for take off.

Plasma rockets don't use a whole lot of fuel as compared to regular rockets however the do require a whole lot of electrical energy.  To get enough energy to the plasma rocket I imagine a network of high powered microwave transmitters "beaming" the energy directly to the ship wirelessly using "rectenna technology"

My kind of space craft would be a space plane that uses extremely powerful plasma rockets.

Because the ship does not need to carry a heavy power source the ship could be remarkably light weight and rectennas have been tested to handle huge currents, like over 100 kilo watts. which is needed to power the trusters

As the space plane goes around the earth many high powered transmitters track the ship until the ship can maintain low earth orbit, at which point the ship can gain speed like an ion craft to be able to break away from the earth to it's destination.

[PmbPhy]

Rockets have always been what we humans have used to get into space BUT traditional rockets are rather expensive and wasteful. Personally I believe a new form of space craft needs to be imagined because what we have today simply wont take us to other stars practically and cheaply.

The problem with that is that what we now know of physics tells us that we can't do it otherwise. While there is some speculation regarding warp drive and wormholes we still can't use those because nothing we know about them allows us to create and use them.

There have also been speculation regarding the use of solar sails but serious consideration shows that they really can never  be used because they're far too impractical. E.g. even the smallest alignment of the sail and the light source will end up moving the sail so far off course as to never reach its target destination.

So I ask you if you can imagine radical new space propellants and technologies, as if you were trying to make a REAL star trek/wars worthy vessel. Just for fun.

A proposed spacecraft which uses nuclear pulse propulsion uses a series of nuclear bombs to propel it. However that's pretty impractical too. The project was called Project Orion. See https://en.wikipedia.org/wiki/Nuclear_pulse_propulsion

I'd say that the most efficient propulsion would use matter and antimatter.

[Kryptid]

Microscopic black holes might be useful for a spacecraft power source, as they can basically convert matter into energy since any matter they consume is turned into Hawking radiation. Creating it and containing it would be a challenge, although the hole could theoretically be given an electrical charge and held in place with an electromagnetic field. That would be quite a heavy power plant, though.

[PmbPhy]

Microscopic black holes might be useful for a spacecraft power source, as they can basically convert matter into energy since any matter they consume is turned into Hawking radiation.

It's a common misconception to think that matter can be converted into energy. That's a misinterpretation of the expression E = mc². For example, what happens in things like nuclear fission and matter-antimatter annihilation is that the form of energy changes from mass-energy to kinetic energy.

Using a black hole to fuel a spaceship is impractical since it can't allow for a change in the momentum of a spacecraft and that's what's needed for propulsion. Also black holes is so massive that it would hamper the acceleration of a spacecraft.

In short it simply won't work.

[Kryptid]

It's a common misconception to think that matter can be converted into energy. That's a misinterpretation of the expression E = mc². For example, what happens in things like nuclear fission and matter-antimatter annihilation is that the form of energy changes from mass-energy to kinetic energy.

So it's a technicality. Mass-energy is still an extreme form of energy storage.

Using a black hole to fuel a spaceship is impractical since it can't allow for a change in the momentum of a spacecraft and that's what's needed for propulsion.

That depends. If you are using the black hole as a source of power (such as heat), you could use that to heat a propellant which is expelled out the back. Alternatively, you could have a reflecting surface surround the black hole on all sides except one, so that Hawking radiation is used to propel the spacecraft.

Also black holes is so massive that it would hamper the acceleration of a spacecraft.

Whether that's a problem or not depends on whether you prefer high acceleration or high top speed.

As an alternative to black holes, I've read that magnetic monopoles are theorized to catalyze proton decay (assuming both phenomena exist). Using hydrogen as an example, a monopole could decay the proton in the nucleus into pions and a positron. The pions decay into gamma rays while the positron would annihilate with the orbiting electron, creating more gamma rays. Sounds like it could be a good energy source, at least in principle.