No unfortunately it is not without spacebridge. Without going into too many details (many of which I dont actually know). The cellular network basically works as a large router that does Network Address Translation (NAT). much like your home router does.
For a quick primer, NAT allows you to have multiple endpoints (every computer / smartphone / tablet) in your house connect to the internet through one public IP address (your IP assigned by the ISP). home routers do this by translating your outgoing requests from your computers internal IP and port to the routers IP and a different port. This works great for home users but has the same affect you are seeing with cell traffic where someone on the internet cannot type in the IP address of your kids iPad on your home WiFi since your router doesnt know which of teh many devices behind it you actually want.
Home routers get around this by allowing you to assign specific pubic IP address and port pairs to go to a specific computer in your house.
Unfortunately this simplified “router” is owned and operated by the cell tower operators (not Hologram but Verizon or T-Mobile). This means they would have to assign this IP and port pair (again over simplified) to accomplish what you are looking for. And without being some huge customer like Amazon they wont do this for you.
To accomplish what you want, your best bet is to use some cloud service like AWS, Azure, Rackspace, etc to operate as a proxy. So basically your website would work like:
Internet request => AWS EC2 running custom webserver and SpaceBridge => Beaglebone Device
Beaglebone Device => AWS ec2 that simply echo’s Beaglebone’s response => Internet user.
Now at this point I would recommend you ask “why put my website code on the Beaglebone and not just on AWS, then my custom code could just ping the beaglebone for data instead of sending a bunch of html tags” And this gets you to the more traditional IoT architecture were you have a cloud computer that is accessible from the internet and also has code to poll or request raw data from your IoT devices.
Best of luck, I hope this helps.