I’ve thought about this, it doesn’t state in any book as far as I know. I would just say it does cancel momentum because that allows for some cool plays, like misty stepping onto the ground at the last second.

ok, that's a cool spell.  am definitely getting that at my fourth level spellcasting for my wizard

Quote from Samuelvonpain

Can you use the spell as trap spell (ex place in front of enemy and it teleport above them and drop them on the ground or a pit)

Normally no. The spell states the creature being brought along must be a willing one. Most enemies would not be a willing target. This does not rule out you may be able to convince them in becoming  willing target. For a slightly convoluted example, you could use 'Charm Person' on a foe, then convince them to 'Dimension Door' with you {caster needs to go with them} and teleport both of you off a cliff {preferably you would have some sort of flight or 'Feather Fall' in your back pocket. Having a Cleric on standby with "Revivify" while not ideal, can also work in a pinch).

Apologies if the reply is a bit off {new to the site and its works}

Can you use the spell on a paralyzed creature, like an ally, i can understand an enemy needing a save but what about an ally that is paralyzed?

Well, I'd say the ally may be paralyzed but his mind would still be willing to go with you...so I'd say yes.

Quote from Heroic_Dad_Mode >>

Does the door stay there for any period of time?

 

Such as go through the door, collect and item, then go back through the door once mroe to my original position?

 Its not really a "door", its just a metaphor.

can i use this like a portal and make some enemy fall until the enemy builds speed and you stop the ability and it smashes into the ground

Wait never mind

This spell is really handy if you’re a Sorceror, or another spellcaster picking up Metamagic Adept and taking Quickened Spell.

If an ally goes down in combat you can rush to the front line using Dash as your action, grab your ally and and jump them back using Dimension Door as your bonus action to a safe location.

Does this spell make noise when you cast it? It has verbal req, but it doesn’t specify, like a whooshing of air or something, when the portal appears.

For beefy casters with an impressive carrying capacity: Hug a boulder + Dimension Door with it to 500 ft above the BBEG's head + release boulder and cast Feather Fall on yourself ;)

Can this spell be used to channel another spell through it? Exemple : i cast DD at the back of the enemies than quick cast firebolt through it so it touch the enemies.

Quote from Orions56 >>

Can this spell be used to channel another spell through it? Exemple : i cast DD at the back of the enemies than quick cast firebolt through it so it touch the enemies.

No. 
There is no "door." That's just the name of this teleportation spell. Read the whole spell again. There's no mention of any door, doorway, portal, or anything of that nature anywhere in there. The name "dimension door" is a hold-over from previous editions where the spell's flavor text described the caster passing through a magical doorway that transported them to another location. That description is no longer here.
It's a teleportation spell. That's it. 

(On a related note:  Everyone, please feel free to cut-and-paste this answer for any future questions about doors, doorways, gates, portals, apertures, hatches, openings, ingresses, egresses, entryways, exits, or anything else like that in relation to this spell. KThx!)

Good rule if thumb is, if they don't explicitly say something that could potentially be important, just ask your DM before the session.

Ive DMed for 20 years, and been playing for maybe 8 months now, and I always just check with my DM.  No one is comfortable with the person who sees a grey area and makes sure it's in their favor.

rules as written though, I believe you're interpreting correctly.  No need to touch.

I know corpses are objects, but could you bring an unconscious creature with you, even if it would be hostile to you?

Interesting question, i'd say a mindless / non intelligent / uncunscious creature is not "willing".

I'd say non-intelligent creatures/mindless creatures could decide against it instinctively, but an unconscious creature wouldn't have a choice in the matter

"... one willing creature..."

Does that mean my buddy can't be holding a bag of mice or something similar when I take him through with me? Would the bag be left behind? Or, because its an object that he is holding, would the bag come through and leave the mice behind?

My Bard just got Dimension Door and our party is trying to figure out how to make a missile out of one of our teammates.

So question... does the door open ON you or like right in front of you (since the creature you can take can be 5 feet away from you)... what I'm thinking is opening a door for a Rouge (who's multi classed) using it to steal something from a desk or a weapon from an opponent .....