# Is there a limit to how big you can make an open ocean ship? **URL:** \ **Category:** Factual Questions\ **Created:** [May 15, 2022, 9:47pm UTC](https://boards.straightdope.com/t/is-there-a-limit-to-how-big-you-can-make-an-open-ocean-ship/964462 "2022-05-15T21:47:35Z")\ **Posts on this page:** 10\ **Page:** 3
**Author:** ![Cervaise](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cervaise/32/16693_2.png) [@Cervaise](https://boards.straightdope.com/u/Cervaise)\ **Post date:** [May 17, 2022, 10:51am UTC](https://boards.straightdope.com/t/is-there-a-limit-to-how-big-you-can-make-an-open-ocean-ship/964462/41 "2022-05-17T10:51:05Z")
> [@JustinC](#): > > Yes, if you want to be able to get through the Panama and Suez Canals - if you can’t, then you are going to go bankrupt. Being able to fit through the Suez Canal is, of course, an evergreen consideration. ---
**Author:** ![JustinC](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/justinc/32/8083_2.png) [@JustinC](https://boards.straightdope.com/u/JustinC)\ **Post date:** [May 19, 2022, 9:00am UTC](https://boards.straightdope.com/t/is-there-a-limit-to-how-big-you-can-make-an-open-ocean-ship/964462/42 "2022-05-19T09:00:05Z")
> [@Cervaise](#): > > Being able to fit through the Suez Canal is, of course, an evergreen consideration. Being unable to fit through the Suez Canal may make your accounts dept. sea red. ---
**Author:** ![gnoitall](https://avatars.discourse-cdn.com/v4/letter/g/bb73d2/32.png) [@gnoitall](https://boards.straightdope.com/u/gnoitall)\ **Post date:** [May 19, 2022, 6:31pm UTC](https://boards.straightdope.com/t/is-there-a-limit-to-how-big-you-can-make-an-open-ocean-ship/964462/43 "2022-05-19T18:31:57Z")
> [@Stranger\_On\_A\_Train](#): > > If you can figure out how to emit uncharged mesons in a specific direction and control their decay you’ll have an unstoppable weapon that can sploosh people from the inside out. You’ve just invented the _Traveller_ meson accelerator cannon. [https://wiki.travellerrpg.com/Meson\_Accelerator](https://wiki.travellerrpg.com/Meson_Accelerator) ETA: I bet you knew that already. ---
**Author:** ![Stranger\_On\_A\_Train](https://avatars.discourse-cdn.com/v4/letter/s/13edae/32.png) [@Stranger\_On\_A\_Train](https://boards.straightdope.com/u/Stranger_On_A_Train)\ **Post date:** [May 19, 2022, 7:04pm UTC](https://boards.straightdope.com/t/is-there-a-limit-to-how-big-you-can-make-an-open-ocean-ship/964462/44 "2022-05-19T19:04:43Z")
> [@gnoitall](#): > > ETA: I bet you knew that already. I did know that and I suspect that Marc Miller and I got it from the same source, which is an otherwise forgettable space opera novel from the ‘Sixties or early ‘Seventies written by some physicist (for a long time I was sure it was Robert Forward but I’ve looked through his oeuvre and there is nothing that matches). The reality is that a meson weapon won’t actually work without a pretty radical retooling of particle physics as we understand it, and the weapon in Traveller fires pions which won’t penetrate the reinforced strong interaction armor plating (though some other exotic mesons can), and the reality is that if you can actually generate the kind of energy need to spontaneously create mesons in large enough quantities to do damage you could use the same energy to propel kinetic slugs to relativistic velocities that would be impossible to dodge and would thoroughly destroy a ship by momentum transfer alone even if the hull could somehow resist penetration. The reality is that it will probably always make more sense to use kinetic weapons than directed energy ones for most warfighting applications, or at least until you develop [a beam that suppresses the electric charge on electrons and protons.](https://scifi.stackexchange.com/questions/189403/can-a-slaver-disintegrator-destroy-a-general-products-hull) Stranger ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [May 19, 2022, 9:00pm UTC](https://boards.straightdope.com/t/is-there-a-limit-to-how-big-you-can-make-an-open-ocean-ship/964462/45 "2022-05-19T21:00:41Z")
Don’t fire both the beams at once, or a current will flow. ---
**Author:** ![Dr.Strangelove](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dr.strangelove/32/6613_2.png) [@Dr.Strangelove](https://boards.straightdope.com/u/Dr.Strangelove)\ **Post date:** [May 19, 2022, 9:30pm UTC](https://boards.straightdope.com/t/is-there-a-limit-to-how-big-you-can-make-an-open-ocean-ship/964462/46 "2022-05-19T21:30:56Z")
> [@Stranger\_On\_A\_Train](#): > > or at least until you develop [a beam that suppresses the electric charge on electrons and protons.](https://scifi.stackexchange.com/questions/189403/can-a-slaver-disintegrator-destroy-a-general-products-hull) As long as we’re going for far out stuff, I was always partial to the hypometric weapons in the _Revelation Space_ series: > **[Hypometric Weapon](https://revelationspace.fandom.com/wiki/Hypometric_Weapon)** > > The Hypometric Weapon was a device which could "delete" matter from a variable spherical area of space, within a range of several light-hours. Contained in a shaft of variable size, the weapon could be equipped on lighthuggers or single crew craft.... Why bother with beams and particles and nonsense when you can just rewrite the coordinates of a region of spacetime? You can delete a ship’s engine or a person’s vital organs. ---
**Author:** ![Stranger\_On\_A\_Train](https://avatars.discourse-cdn.com/v4/letter/s/13edae/32.png) [@Stranger\_On\_A\_Train](https://boards.straightdope.com/u/Stranger_On_A_Train)\ **Post date:** [May 19, 2022, 10:10pm UTC](https://boards.straightdope.com/t/is-there-a-limit-to-how-big-you-can-make-an-open-ocean-ship/964462/47 "2022-05-19T22:10:37Z")
> [@Dr.Strangelove](#): > > Why bother with beams and particles and nonsense when you can just rewrite the coordinates of a region of spacetime? You can delete a ship’s engine or a person’s vital organs. Well, that would certainly break general relativity and probably cause some kind of cascading effect in spacetime as a whole. I think I’d prefer not to rend the fabric of the universe open lest some Cthuloid foulness emerge and turn my brain into purple tapioca just because I glanced at it. I have enough problems with reality as it is. Stranger ---
**Author:** ![Dr.Strangelove](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dr.strangelove/32/6613_2.png) [@Dr.Strangelove](https://boards.straightdope.com/u/Dr.Strangelove)\ **Post date:** [May 19, 2022, 10:19pm UTC](https://boards.straightdope.com/t/is-there-a-limit-to-how-big-you-can-make-an-open-ocean-ship/964462/48 "2022-05-19T22:19:50Z")
Well, _suuure_, but at least general relativity is a local theory and even some kind of rip in spacetime is only going to expand at the speed of light. But suppressing electric charge breaks quantum electrodynamics, and that means you’re breaking at least a few _global_ gauge symmetries. I don’t like the idea of accidentally causing all matter in the universe to disintegrate all at once. ---
**Author:** ![Stranger\_On\_A\_Train](https://avatars.discourse-cdn.com/v4/letter/s/13edae/32.png) [@Stranger\_On\_A\_Train](https://boards.straightdope.com/u/Stranger_On_A_Train)\ **Post date:** [May 19, 2022, 10:40pm UTC](https://boards.straightdope.com/t/is-there-a-limit-to-how-big-you-can-make-an-open-ocean-ship/964462/49 "2022-05-19T22:40:19Z")
The gravitational effects from a discontinuity in spacetime would only propagate at _c_, but the actual discontinuity itself might be able to expand at any speed depending on how the plenum of spacetime actually works (we have no idea). I wouldn’t say that suppressing the electric charge ‘breaks’ QED so much as that the theory can no longer predict the effect because of the discontinuity. But suddenly suppressing the charge would only release as much energy as is stored in the electromagnetic field local to that charge; depending on the material you’re talking about energies on close order of about 500 kJ/mol, comparable to a powerful chemical explosive. However, if you are ‘deleting’ mass there may be an enormous and hard to characterize redistribution of gravitational potential; like pulling a cornerstone out of a foundation or the keystone out of an arch bridge, it can weaken the entire structure and cause it to collapse regardless of how strong it was in the original configuration. Gravitational potential is actually really difficult to characterize in a global sense as it depends upon the frame of reference, so what effect this might have in reality is hard to grasp but I suspect we’re talking about orders of magnitude greater redistribution of the stress-energy-momentum pseudotensor. I certainly wouldn’t want to be nearby when someone tries this experiment, and by “nearby” I mean in the same galaxy. Stranger ---
**Author:** ![eburacum45](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/eburacum45/32/8690_2.png) [@eburacum45](https://boards.straightdope.com/u/eburacum45)\ **Post date:** [May 23, 2022, 11:20am UTC](https://boards.straightdope.com/t/is-there-a-limit-to-how-big-you-can-make-an-open-ocean-ship/964462/50 "2022-05-23T11:20:10Z")
> [@Dr.Strangelove](#): > > And while I don’t know if they did any back-of-the-envelope calculations when sketching out the ship, it’s at least past the “obviously impossible” level in terms of heat rejection The basic design was conceived by Charles Pellegrino for his own series of novels; here’s a description by Winchell Chung discussing some of the advantages and disadvantages of the design. see [http://www.projectrho.com/public\_html/rocket/slowerlight3.php#id--Go\_Fast--Nearlight\_Starships--Avatar\_ISV\_Venture\_Star](http://www.projectrho.com/public_html/rocket/slowerlight3.php#id--Go_Fast--Nearlight_Starships--Avatar_ISV_Venture_Star) and [http://www.projectrho.com/public\_html/rocket/slowerlight3.php#valkyrie](http://www.projectrho.com/public_html/rocket/slowerlight3.php#valkyrie) [Previous page](https://boards.straightdope.com/t/is-there-a-limit-to-how-big-you-can-make-an-open-ocean-ship/964462.md?page=2)