You're worryingly good at this...Nooooo.... you can't do this, think of all the earth leaking out of the cable! You're going to destroy the planet if you don't connect it into something - why do you think earth is always grounded? It's so the earth goes back into the Earth obviously, otherwise all our planet will escape into the atmosphere and we'll turn into a gas planet like jupiter or saturn. Is that what you want? Cos that's what'll happen.
Fortunately I can sell you some end caps for the cable which will stop this from occurring. My crimps look a lot like these cable ends (£8.99 for 70) but in fact they are made of an adamantium/unobtanium alloy to ensure they are strong enough to withstand the various geological forces produced by an ungrounded earth cable. (think how strong an earthquake is - would you trust a standard cable end to hold back that force??).
£8,999 per pair. A bargain for the peace of mind that you are not going to end all life as we know it.