Deleting a hard link's tail file changes the change time of the head or vice versa. Why?

*Note: Question although says vice versa but it really does not have any meaning since both of them point to the same inode and its not possible to say which is head and which is tail.* Say I have a file hlh.txt [root@FREL ~]# fallocate -l 100 hlh.txt Now if I see the change time for hlh.txt [root@FREL ~]# stat hlh.txt File: hlh.txt Size: 100 Blocks: 8 IO Block: 4096 regular file Device: fc00h/64512d Inode: 994 Links: 1 Access: (0644/-rw-r--r--) Uid: ( 0/ root) Gid: ( 0/ root) Context: unconfined_u:object_r:admin_home_t:s0 Access: 2023-01-11 01:43:05.469703330 -0500 Modify: 2023-01-11 01:43:05.469703330 -0500 Change: 2023-01-11 01:43:05.469703330 -0500 Birth: 2023-01-11 01:43:05.469703330 -0500 Creating hard link [root@FREL ~]# ln hlh.txt hlt.txt Since both hlh.txt and hlt.txt points to same inode, so change time would be the ctime of the hard link tail file which is understood. [root@FREL ~]# stat hlt.txt File: hlt.txt Size: 100 Blocks: 8 IO Block: 4096 regular file Device: fc00h/64512d Inode: 994 Links: 2 Access: (0644/-rw-r--r--) Uid: ( 0/ root) Gid: ( 0/ root) Context: unconfined_u:object_r:admin_home_t:s0 Access: 2023-01-11 01:43:05.469703330 -0500 Modify: 2023-01-11 01:43:05.469703330 -0500 Change: 2023-01-11 01:44:05.316842644 -0500 Birth: 2023-01-11 01:43:05.469703330 -0500 But if I unlink the head file, that changes ctime of the file as well. Why? I mean all we did is delete the head, **what significance does change time have here internally. Why does it need to be change?** [root@FREL ~]# unlink hlh.txt [root@FREL ~]# [root@FREL ~]# stat hlt.txt File: hlt.txt Size: 100 Blocks: 8 IO Block: 4096 regular file Device: fc00h/64512d Inode: 994 Links: 1 Access: (0644/-rw-r--r--) Uid: ( 0/ root) Gid: ( 0/ root) Context: unconfined_u:object_r:admin_home_t:s0 Access: 2023-01-11 01:43:05.469703330 -0500 Modify: 2023-01-11 01:43:05.469703330 -0500 Change: 2023-01-11 01:47:49.588364704 -0500 Birth: 2023-01-11 01:43:05.469703330 -0500